Category Archives: Code samples

Code samples for my book on Querying data with Transact-SQL (MCSA 70-761), chapter 3

Posted on October 9, 2019 by Robert

USE TestDB
GO

/* Create database programmability objects by using Transact-SQL */

-- views
-- 001
WITH o 
AS (	SELECT * 
	FROM Sales.Orders)
SELECT	*
FROM	o

-- 002
CREATE VIEW vwEmployeeFirstName 
AS 
SELECT	FirstName 
FROM	Employees; 

-- 003
SELECT  * 
FROM    vwEmployeefirstname;

-- 004
GO
CREATE OR ALTER VIEW vwEmployeeFirstName 
AS 
SELECT	FirstName 
FROM	Employees; 

-- 005
CREATE VIEW vwEmployeesEngineering
AS 
SELECT	*
FROM	dbo.Employees
WHERE	Department = 'Engineering'
GO
SELECT * 
FROM vwEmployeesEngineering

-- 006
ALTER TABLE Employees ADD AdditionalColumn varchar(100) NULL
GO
CREATE OR ALTER VIEW vwEmployeesEngineering
AS 
SELECT	FirstName, LastName, AdditionalColumn
FROM	dbo.Employees
WHERE	Department = 'Engineering'
GO
SELECT * 
FROM vwEmployeesEngineering
GO
ALTER TABLE Employees DROP COLUMN AdditionalColumn 
GO
SELECT * 
FROM vwEmployeesEngineering

-- 007
CREATE OR ALTER VIEW vwEmployeesEngineering
WITH SCHEMABINDING
AS 
SELECT	FirstName, LastName, AdditionalColumn
FROM	dbo.Employees
WHERE	Department = 'Engineering'

-- 008
EXEC sp_refreshview 'vwEmployeesEngineering'

-- 009
CREATE OR ALTER VIEW vwEmployeesEngineering
WITH ENCRYPTION
AS 
SELECT	FirstName, LastName, AdditionalColumn
FROM	dbo.Employees
WHERE	Department = 'Engineering'

-- 010
SELECT	object_name(id), text
FROM	sys.syscomments

-- 011
UPDATE	vwEmployeesEngineering
SET	FirstName = 'Bobby'
WHERE	FirstName = 'Bob'

-- 012
UPDATE	vwEmployeesEngineering
SET	Department = 'Sales'
WHERE	FirstName = 'Bobby'

-- 013
UPDATE	dbo.Employees
SET	FirstName = 'Bob', Department = 'Engineering'
WHERE	FirstName = 'Bobby'
GO
CREATE OR ALTER VIEW vwEmployeesEngineering
AS 
SELECT	*
FROM	dbo.Employees
WHERE	Department = 'Engineering'
WITH CHECK OPTION

-- 014
INSERT INTO [dbo].[vwEmployeesEngineering]
([FirstName], [LastName], [Address], [Salary], [Department])
VALUES ('James' ,'Jameson' ,'Somewhere in Ireland' ,1000 ,'sales')

-- 015
DELETE FROM vwEmployeesEngineering WHERE FirstName = 'James'

-- 016
DROP VIEW IF EXISTS vwEmployeesEngineering

/* Implement input and output parameters in stored procedures */

-- 017
CREATE OR ALTER PROC procGetEmployeeInformation 
AS
BEGIN 
	--explanation of what the stored proc does 
	SET NOCOUNT ON; 
	SELECT	* 
	FROM	Employees; 
END

-- 018
EXEC procGetEmployeeInformation

-- 019
DROP PROC IF EXISTS procGetEmployeeInformation

-- 020
CREATE PROC procGetEmployeeID 
	@FirstName	varchar(100) 
	,@LastName	varchar(50) 
	,@Address	varchar(100) 
AS 
BEGIN 
	SELECT	EmployeeID
	FROM	Employees
	WHERE	FirstName = @FirstName 
		AND LastName = @LastName 
		AND Address = @Address; 
END;

-- 021
EXEC procGetEmployeeID @FirstName = 'Bob', @LastName = 'Jackson', @Address = 'Under the bridge'

EXEC procGetEmployeeID 'Bob', 'Jackson', 'Under the bridge'

-- 022
CREATE OR ALTER PROC procGetEmployeeID 
	@FirstName	varchar(100) 
	,@LastName	varchar(50) 
	,@Address	varchar(100)
	,@EmployeeID tinyint OUTPUT 
AS 
BEGIN 
	SELECT	@EmployeeID = EmployeeID
	FROM	Employees
	WHERE	FirstName = @FirstName 
			AND LastName = @LastName 
			AND Address = @Address; 
END;

-- 023
DECLARE @EmployeeID tinyint
EXEC procGetEmployeeID 'Bob', 'Jackson', 'Under the bridge', @EmployeeID = @EmployeeID OUTPUT
SELECT @EmployeeID

-- 024
CREATE PROC procLogicalTest 
@parameter int 
AS 
BEGIN 
	IF @parameter = 1 
	BEGIN 
		EXEC proc1;
	END 
	ELSE 
	BEGIN 
		EXEC proc2
	END 
END;

/* functions */

-- 025
CREATE FUNCTION dbo.fn_rand ()
RETURNS INT
AS
BEGIN
	RETURN RAND()
END

-- 026
CREATE OR ALTER FUNCTION dbo.fn_doubler (@a int)
RETURNS INT
AS
BEGIN
	RETURN @a * 2
END

-- 027
SELECT dbo.fn_doubler (18)

-- 028
SELECT	FirstName
	, LastName
	, dbo.fn_doubler(salary) as TwiceTheSalary
FROM	dbo.Employees

-- 029
CREATE FUNCTION dbo.fn_GetListOfEmployees(@Department AS varchar(100))  
RETURNS TABLE 
AS 
RETURN 
   ( 
   SELECT	FirstName + ' ' + LastName AS FullName, Salary
   FROM	Employees e 
   WHERE	e.Department = @Department 
   ) 

-- 030
SELECT * FROM dbo.fn_GetListOfEmployees('Sales')

-- 031
CREATE OR ALTER FUNCTION dbo.fn_name (...)
RETURNS @return_table TABLE
AS
BEGIN
	--some statements

	--a statement to fill the table variable
	INSERT @return_table
	SELECT ...
	
	--return the table variable to the calling statement
	RETURN
END

-- 032
CREATE dbo.ManagersAllTheWayToTheTop (@employeeid tinyint)
RETURNS @tbl_managers TABLE 
(
	Name		varchar(151)
	, Manager	varchar(151)
	,Level		tinyint
)
BEGIN
	WITH Employee_CTE AS (
		SELECT	EmployeeID, ManagerID, 0 as Level
		FROM	Employees
		WHERE	FirstName = 'Bob'
	
		UNION ALL
		SELECT	e1.EmployeeID, e1.ManagerID, e2.level + 1
		FROM	Employees e1
			INNER JOIN Employee_CTE e2 ON e1.EmployeeID = e2.ManagerID
	)
	,
	Distinct_CTE AS (
		SELECT DISTINCT EmployeeID,  ManagerID, Level
		FROM Employee_CTE)
	INSERT INTO @tbl_managers
	SELECT	e2.FirstName + ' ' + e2.LastName AS Name
	, e3.FirstName + ' ' + e3.LastName AS Manager, Level
	FROM	Distinct_CTE e1
		INNER JOIN Employees e2 ON e1.employeeID = e2.EmployeeID
		LEFT OUTER JOIN Employees e3 ON e1.ManagerID = e3.EmployeeID
	ORDER BY Level, Name
	RETURN
END

GO

SELECT * FROM dbo.managersallthewaytothetop(1)

DROP FUNCTION IF EXISTS dbo.ManagersAllTheWayToTheTop

-- 033
CREATE OR ALTER FUNCTION dbo.fn_doubler (@a int)
RETURNS INT
AS
BEGIN
	RETURN @a * 2
END
GO

SELECT OBJECTPROPERTYEX(OBJECT_ID('dbo.fn_doubler'), 'IsDeterministic')

-- 034
CREATE OR ALTER FUNCTION dbo.fn_doubler (@a int)
RETURNS INT
WITH SCHEMABINDING
AS
BEGIN
	RETURN @a * 2
END
GO

SELECT OBJECTPROPERTYEX(OBJECT_ID('dbo.fn_doubler'), 'IsDeterministic')

/* Implement error handling and transactions */

--For more information on isolation levels, see: https://docs.microsoft.com/en-us/sql/connect/jdbc/understanding-isolation-levels?view=sql-server-2016 

-- 035
USE TestDB
GO

DROP TABLE IF EXISTS dbo.OrderLines
DROP TABLE IF EXISTS dbo.Orders
DROP TABLE IF EXISTS dbo.Customers
GO

CREATE TABLE dbo.Customers(
	CustomerID	int IDENTITY(1,1) NOT NULL,
	FirstName	varchar(100) NOT NULL,
	LastName	varchar(100) NOT NULL,
	[Address]	varchar(100) NOT NULL,
	PRIMARY KEY CLUSTERED (CustomerID)
)

CREATE TABLE dbo.Orders(
	OrderID	int IDENTITY(1,1) NOT NULL,
	CustomerID	int NOT NULL,
	OrderDate	datetime NOT NULL,
	SalesAmount 	money NOT NULL,
	PRIMARY KEY CLUSTERED (OrderID )
) 

CREATE TABLE dbo.OrderLines(
	OrderID	int NOT NULL,
	OrderLineID	int IDENTITY(1,1) NOT NULL,
	Item		varchar(100) NOT NULL,
	Amount		int NOT NULL,
	LineAmount	money NOT NULL,
PRIMARY KEY CLUSTERED (OrderID, OrderLineID )
) 

GO

ALTER TABLE dbo.Orders ADD CONSTRAINT FK_customerID 
FOREIGN KEY (CustomerID) REFERENCES dbo.Customers(CustomerID)

ALTER TABLE dbo.OrderLines ADD CONSTRAINT FK_OrderID 
FOREIGN KEY (OrderID) REFERENCES dbo.Orders(OrderID)

-- 036
INSERT dbo.Customers VALUES ('Bob', 'Jackson', 'Main street 1, Dallas')

-- 037
SET IMPLICIT_TRANSACTIONS ON

INSERT dbo.Customers VALUES ('Frank', 'Smith', 'Second street 2, Miami')

-- 038
SELECT	*
FROM	Customers

-- 039
SELECT	*
FROM	Customers WITH (NOLOCK)

-- 040
DBCC OPENTRAN();

-- 041
SELECT	session_id, open_transaction_count
FROM	sys.dm_exec_sessions
WHERE	session_id > 50;

-- 042
SELECT @@TRANCOUNT 

-- 043
COMMIT TRANSACTION

-- 044
SET IMPLICIT_TRANSACTIONS OFF

-- 045
BEGIN TRANSACTION
INSERT dbo.Customers VALUES ('Joe', 'Johnson', 'Third Avenue 3, New York')
COMMIT TRANSACTION

-- 046
BEGIN TRAN MyTran WITH MARK 'StartOfTransaction'

-- 047
ROLLBACK

/* Nesting transactions */

-- 048
INSERT Orders (CustomerID, OrderDate, SalesAmount)
VALUES (1, GETDATE(), 10.00)

-- 049
UPDATE Orders SET SalesAmount = 10.00

BEGIN TRAN 
	SELECT @@Trancount AS 'Transaction level'
	UPDATE Orders 
SET SalesAmount = SalesAmount + 1 
WHERE orderid = 1
		BEGIN TRAN
			SELECT @@Trancount AS 'Transaction level'
			UPDATE Orders 
SET SalesAmount = SalesAmount + 1 
WHERE orderid = 1
			BEGIN TRAN
				SELECT @@Trancount AS 'Transaction level'
				UPDATE Orders 
SET SalesAmount = SalesAmount + 1 
WHERE orderid = 1
			COMMIT TRAN
			SELECT @@Trancount AS 'Transaction level'
		COMMIT TRAN
	SELECT @@Trancount AS 'Transaction level'
COMMIT TRAN

SELECT	*
FROM	Orders
WHERE	orderid = 1

-- 050
UPDATE Orders SET SalesAmount = 10.00

BEGIN TRAN 
	SELECT @@Trancount AS 'Transaction level'
	UPDATE Orders 
SET SalesAmount = SalesAmount + 1 
WHERE orderid = 1
		BEGIN TRAN
			SELECT @@Trancount AS 'Transaction level'
			UPDATE Orders 
SET SalesAmount = SalesAmount + 1 
WHERE orderid = 1
			BEGIN TRAN
				SELECT @@Trancount AS 'Transaction level'
				UPDATE Orders 
SET SalesAmount = SalesAmount + 1 
WHERE orderid = 1
			COMMIT TRAN
			SELECT @@Trancount AS 'Transaction level'
		ROLLBACK TRAN --<<<< Only this line has changed
	SELECT @@Trancount AS 'Transaction level'
COMMIT TRAN

SELECT	*
FROM	Orders
WHERE	orderid = 1

/* Named transaction */
-- 051
UPDATE Orders SET SalesAmount = 10.00

BEGIN TRAN MyFirstTransaction
	SELECT @@Trancount AS 'Transaction level'
	UPDATE Orders 
	SET SalesAmount = SalesAmount + 1 
	WHERE orderid = 1
		BEGIN TRAN MySecondTransaction
			SELECT @@Trancount AS 'Transaction level'
			UPDATE Orders 
			SET SalesAmount = SalesAmount + 1 
			WHERE orderid = 1
			BEGIN TRAN MyThirdTransaction
				SELECT @@Trancount AS 'Transaction level'
				UPDATE Orders 
				SET SalesAmount = SalesAmount + 1 
				WHERE orderid = 1
			COMMIT TRAN MyThirdTransaction
			SELECT @@Trancount AS 'Transaction level'
		ROLLBACK TRAN MySecondTransaction
	SELECT @@Trancount AS 'Transaction level'
COMMIT TRAN MyFirstTransaction

SELECT	*
FROM	Orders
WHERE	orderid = 1

-- 052
ROLLBACK TRAN

/* savepoints */

-- 053
UPDATE Orders SET SalesAmount = 10.00

BEGIN TRAN
	UPDATE Orders 
	SET SalesAmount = SalesAmount + 1 
	WHERE orderid = 1

	UPDATE Orders 
	SET SalesAmount = SalesAmount + 1 
	WHERE orderid = 1

	SAVE TRANSACTION MyFirstSavepoint

	UPDATE Orders 
	SET SalesAmount = SalesAmount + 1 
	WHERE orderid = 1

	ROLLBACK TRANSACTION MyFirstSavepoint

COMMIT TRAN 

SELECT	*
FROM	Orders
WHERE	orderid = 1

-- what is rolled back?
-- 054
EXEC xp_cmdshell 'mkdir d:\Test_directory'

-- 055
BEGIN TRAN
EXEC xp_cmdshell 'mkdir d:\Test_directory'
ROLLBACK

-- 056
BEGIN TRAN
CREATE DATABASE TooBad
ROLLBACK

-- 057
SET NOCOUNT ON
DECLARE @MyToughVariable INT
SET @MyToughVariable = 1
SELECT IDENT_CURRENT('Customers') AS 'Current identity'

BEGIN TRAN
	SET @MyToughVariable = 2
	SELECT @MyToughVariable AS 'Variable'
	CREATE TABLE MysteryTable (MysterID INT IDENTITY, Mystery VARCHAR(100))
	INSERT MysteryTable VALUES ('Who killed Kennedy?')
	SELECT *
	FROM MysteryTable
	ALTER TABLE dbo.Customers ADD DateOfBirth DATETIME NULL
	
	INSERT dbo.Customers 
VALUES ('Serena', 'Baker', 'Broadway, New York', GETDATE())
	
SELECT * FROM Customers
ROLLBACK TRAN

SELECT @MyToughVariable AS 'Variable'

SELECT IDENT_CURRENT('Customers') AS 'Current identity'

SELECT *
FROM dbo.Customers

SELECT *
FROM MysteryTable

-- 058
SET XACT_ABORT ON

-- 059
DROP TABLE IF EXISTS MysteryTable;

-- application timeout example
-- 060
USE TestDB
GO
SET XACT_ABORT ON
BEGIN TRAN
	CREATE TABLE MysteryTable (MysterID INT IDENTITY, Mystery VARCHAR(100))
	INSERT MysteryTable VALUES ('Who killed Kennedy?')

	WAITFOR DELAY '00:01'
COMMIT TRAN

-- 061
SELECT * FROM MysteryTable;

/* foreign key error example */
-- 062
SET XACT_ABORT ON

BEGIN TRAN
	DECLARE @Order_id INT

	INSERT Orders (CustomerID, OrderDate, SalesAmount)
	VALUES (2, GETDATE(), 50.00)

	SET @Order_id = @@IDENTITY

	INSERT OrderLines (OrderID, Item, Amount, LineAmount)
	VALUES (@Order_id , 'Bag of screws', 4, 10.00)

	INSERT OrderLines (OrderID, Item, Amount, LineAmount)
	VALUES (@Order_id + 1, 'Screwdriver', 1, 10.00)

COMMIT

/* Implement TRY…CATCH error handling with Transact-SQL */

-- 063
BEGIN TRY
   DECLARE	@MyVariable INT
   SET		@MyVariable = 5
   SET		@MyVariable = @MyVariable/0
   PRINT	'This line of code will not be executed'
END TRY
BEGIN CATCH 
   PRINT	'A useful error message'
END CATCH

-- 064
BEGIN TRY
	DECLARE	@MyVariable INT;
	SET		@MyVariable = 5;
	SET		@MyVariable = @MyVariable/0;
	PRINT	'This line of code will not be executed';
END TRY
BEGIN CATCH 
    SELECT  
        ERROR_NUMBER() AS ErrorNumber,  
        ERROR_SEVERITY() AS ErrorSeverity,  
        ERROR_STATE() AS ErrorState,  
        ISNULL(ERROR_PROCEDURE(), 'Not inside a stored proc') AS ErrorProcedure,  
        ERROR_LINE() AS ErrorLine,  
        ERROR_MESSAGE() AS ErrorMessage;  
END CATCH

/* THROW  */
-- 065
BEGIN TRY
	DECLARE	@MyVariable INT;
	SET		@MyVariable = 5;
	SET		@MyVariable = @MyVariable/0;
	PRINT	'This line of code will not be executed';
END TRY
BEGIN CATCH 
	PRINT	'A useful error message';
	THROW;
	PRINT	'This line of code will not be executed either';
END CATCH ;

-- 066
THROW 50000, 'A useful error message', 0;

-- 067
DECLARE @msg_number 	INT = 50000
	,@msg_text	NVARCHAR(2048) = N'A useful error message'
	,@msg_state	TINYINT = 0;

THROW @msg_number, @msg_text, @msg_state;

-- 068
SET @msg_text = 'This error occurred on ' 
		+ CONVERT(varchar(19),getdate(), 20) + ', process id ' 
		+ CONVERT(varchar(10),@@SPID);

-- 069
USE master;  
GO  
EXEC sp_addmessage @msgnum = 50001
,@severity = 16
,@msgtext = 'This error occurred on %s , process id %s.'
,@lang = 'us_english';  

EXEC sp_addmessage @msgnum = 50001
,@severity = 16
,@msgtext = 'Dieser Fehler ist aufgetreten %1!,Prozess ID %2!'
,@lang = 'German';  
GO

-- 070
DECLARE @msg_number 	INT = 50001
	,@msg_text	NVARCHAR(2048) 
	,@msg_state	TINYINT = 0;

SET LANGUAGE German; 

SET @msg_text = FORMATMESSAGE(50001, CONVERT(varchar(19),getdate(), 20), CONVERT(varchar(10),@@SPID));

THROW @msg_number, @msg_text, @msg_state;

-- 071
DECLARE @msg_number INT = 50001
	,@msg_text	NVARCHAR(2048) 
	,@msg_state	TINYINT = 0;

SET LANGUAGE us_english; 

SET @msg_text = FORMATMESSAGE(50001, CONVERT(varchar(19),getdate(), 20), CONVERT(varchar(10),@@SPID));

THROW @msg_number, @msg_text, @msg_state;

/* RAISERROR */
-- 072
DECLARE @date		varchar(19) = CONVERT(varchar(19),getdate(), 20)
	,@process_id 	varchar(10) = CONVERT(varchar(10),@@SPID);

RAISERROR (50001, 16, 1, @date, @process_id);
GO 

DECLARE @date		varchar(19) = CONVERT(varchar(19),getdate(), 20)
	,@process_id 	varchar(10) = CONVERT(varchar(10),@@SPID);

RAISERROR ('This error occurred on %s , process id %s.', 16, 1, @date, @process_id);
GO 

DECLARE @date		varchar(19) = CONVERT(varchar(19),getdate(), 20)
	,@process_id 	varchar(10) = CONVERT(varchar(10),@@SPID)
	,@msg_text  	nvarchar (100) = N'This error occurred on %s , process id %s.';

RAISERROR (@msg_text, 16, 1, @date, @process_id);
GO

-- 073
DECLARE @date		varchar(19) = CONVERT(varchar(19),getdate(), 20)
	,@process_id 	varchar(10) = CONVERT(varchar(10),@@SPID)
	,@msg_text  	nvarchar (100) = N'This error occurred on %s , process id %s.';

RAISERROR (@msg_text, 20, 1, @date, @process_id) WITH LOG;
GO

-- 074
EXEC sp_dropmessage @msgnum = 50001, @lang = 'all';

-- 075
DROP TABLE IF EXISTS MysteryTable;

DECLARE @date		varchar(19) = CONVERT(varchar(19),getdate(), 20)
	,@process_id 	varchar(10) = CONVERT(varchar(10),@@SPID);

SET XACT_ABORT OFF;
BEGIN TRAN

	CREATE TABLE MysteryTable (MysterID INT IDENTITY, Mystery VARCHAR(100));
	INSERT MysteryTable VALUES ('Who killed Kennedy?');

	THROW 50000, 'A useful error message', 0;
	--RAISERROR (50001, 16, 1, @date, @process_id);

COMMIT
GO
SELECT * FROM MysteryTable;

/* Implement transaction control in conjunction with error handling in stored procedures */
-- 076
CREATE PROCEDURE usp_my_stored_proc @MyVariable <data_type>
AS 
BEGIN
	SET XACT_ABORT, NOCOUNT ON;

	BEGIN TRY
	
		BEGIN TRAN
		
--Validate input parameter(s)
		IF @MyVariable ...

		--Actual work
		... 
		
COMMIT TRAN
	END TRY
	BEGIN CATCH
		IF @@TRANCOUNT > 0 ROLLBACK TRAN
		-- error message, either THROW, RAISERROR or custom error logging code
	END CATCH
END

-- 077
CREATE PROC usp_inner_proc
AS
BEGIN
	SET XACT_ABORT ON
	BEGIN TRY
		BEGIN TRAN
			SELECT 5/0
		COMMIT TRAN
	END TRY
	BEGIN CATCH
		ROLLBACK;
		THROW
	END CATCH
END
GO
CREATE PROC usp_outer_proc
AS
BEGIN
	SET XACT_ABORT ON
	BEGIN TRY
		BEGIN TRAN
			EXEC usp_inner_proc
		COMMIT TRAN
	END TRY
	BEGIN CATCH
		ROLLBACK;
		THROW
	END CATCH
END
GO
EXEC usp_outer_proc

-- 078
ALTER PROC usp_outer_proc
AS
BEGIN
	SET XACT_ABORT ON
	BEGIN TRY
		BEGIN TRAN
			EXEC usp_inner_proc
		COMMIT TRAN
	END TRY
	BEGIN CATCH
		IF @@TRANCOUNT > 0 ROLLBACK;
		THROW
	END CATCH
END

-- 079
DROP PROC IF EXISTS usp_inner_proc
DROP PROC IF EXISTS usp_outer_proc

--For more information about error handling, read the eBook Defensive Database Programming with SQL Server, by Alex Kuznetsov, available for free at: https://www.red-gate.com/library/defensive-database-programming 

/* Implement data types and NULLs */
DECLARE @MyVariable DECIMAL(5,2)

DECLARE @MyVariable FLOAT(n)

-- 080
DECLARE @MyVariable real = 100.123456789

SELECT STR(@MyVariable, 6,2)

--text
DECLARE @MyVariable CHAR(4) = 'Text'

DECLARE @MyVariable NCHAR(4) = N'Text'

-- 081
DECLARE @MyVariable uniqueidentifier = NEWID()
SELECT @MyVariable

--rowversion
-- 082
CREATE TABLE Table1 (Column1 smallint, Column2 rowversion)

INSERT Table1 (Column1) VALUES (1)
SELECT * FROM Table1
UPDATE Table1 SET Column1 = 2 
SELECT * FROM Table1

--implicit conversion
-- 083
DECLARE @MyVariable INT = '45'

SET @MyVariable = @MyVariable + 10

IF @MyVariable > '50'
PRINT 'Yep, it''s bigger.'

-- 084
DECLARE @MyVariable VARCHAR(100) = 'My favourite number is '

SET @MyVariable = @MyVariable + 16

SELECT @MyVariable

-- The complete data type precedence list: https://docs.microsoft.com/en-us/sql/t-sql/data-types/data-type-precedence-transact-sql?view=sql-server-2016 
-- Implicit conversions: https://docs.microsoft.com/en-us/sql/t-sql/data-types/data-type-conversion-database-engine?view=sql-server-2016 

-- 085
SELECT 2/5
SELECT 2000000000 + 2000000000

-- 086
SELECT 2000000000 + 4000000000

-- 087
DECLARE @MyVariable numeric(3,2) = 4.63

SELECT	@MyVariable AS column1
INTO	Type_check_table

/* ISNULL versus COALESCE */
-- 088
DECLARE @MyNULLVariable VARCHAR(100)
	,@MyNonNULLVariable VARCHAR(100) = 'Original value'

SELECT	ISNULL(@MyNULLVariable, 'Replacement value')
	,ISNULL(@MyNonNULLVariable, 'Replacement value')

-- 089
DECLARE @MyNULLVariable VARCHAR(100)
	,@MyNonNULLVariable VARCHAR(100) = 'Original value'

SELECT	COALESCE(@MyNULLVariable, @MyNonNULLVariable, 'Replacement value')

-- 090
SELECT	CASE
		WHEN @MyNULLVariable IS NOT NULL THEN @MyNULLVariable
		WHEN @MyNonNULLVariable IS NOT NULL THEN @MyNonNULLVariable
		ELSE 'Replacement value'
	END

-- 091
DECLARE @MyDateVariable date = '2018-10-05'
	,@MyDateTimeVariable datetime = '2018-10-05 11:07'

SELECT ISNULL(@MyDateVariable, @MyDateTimeVariable)
	, COALESCE(@MyDateVariable, @MyDateTimeVariable) 

-- 092
DROP TABLE IF EXISTS Type_check_table

DECLARE @MyDateVariable date = '2018-10-05'

SELECT	ISNULL(@MyDateVariable, '2018-10-05 11:07') AS column1
		,ISNULL('2018-10-05 11:07', @MyDateVariable) AS column2
		,ISNULL(@MyDateVariable, @MyDateVariable) AS column3
		,ISNULL('2018-10-05 11:07', '2018-10-05 11:07') AS column4
INTO	Type_check_table

SELECT	c.name, t.name, c.max_length, c.precision, c.scale, c.is_nullable
FROM	sys.columns c
		INNER JOIN sys.types t ON c.system_type_id = t.system_type_id
WHERE	object_id = object_id('Type_check_table')

DROP TABLE IF EXISTS Type_check_table

-- 093
SELECT	*
INTO	Customers_copy
FROM	WideWorldImporters.sales.Customers

SELECT	*
INTO	orders_copy
FROM	WideWorldImporters.sales.orders

-- 094
SELECT		CustomerName
		,ISNULL((	SELECT MAX(OrderDate) 
FROM Orders_copy o 
WHERE o.CustomerID = c.CustomerID), '1900-1-1')
FROM		Customers_copy c

SELECT		CustomerName
		,COALESCE((	SELECT MAX(OrderDate) 
FROM Orders_copy o 
WHERE o.CustomerID = c.CustomerID), '1900-1-1')
FROM		Customers_copy c

-- 095
SELECT		CustomerName
		,CASE WHEN (	SELECT MAX(OrderDate) 	
FROM Orders_copy o 
WHERE o.CustomerID = c.CustomerID) IS NOT NULL 
THEN (
SELECT MAX(OrderDate) 
FROM Orders_copy o 
WHERE o.CustomerID = c.CustomerID)
			ELSE '1900-1-1'
END
FROM	Customers_copy c

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USE TestDB

/* Create database programmability objects by using Transact-SQL */

-- views

-- 001

WITH o

AS ( SELECT *

FROM Sales.Orders)

SELECT *

FROM o

-- 002

CREATE VIEW vwEmployeeFirstName

SELECT FirstName

FROM Employees;

-- 003

SELECT *

FROM vwEmployeefirstname;

-- 004

CREATE OR ALTER VIEW vwEmployeeFirstName

SELECT FirstName

FROM Employees;

-- 005

CREATE VIEW vwEmployeesEngineering

SELECT *

FROM dbo.Employees

WHERE Department = 'Engineering'

SELECT *

FROM vwEmployeesEngineering

-- 006

ALTER TABLE Employees ADD AdditionalColumn varchar(100) NULL

CREATE OR ALTER VIEW vwEmployeesEngineering

SELECT FirstName, LastName, AdditionalColumn

FROM dbo.Employees

WHERE Department = 'Engineering'

SELECT *

FROM vwEmployeesEngineering

ALTER TABLE Employees DROP COLUMN AdditionalColumn

SELECT *

FROM vwEmployeesEngineering

-- 007

CREATE OR ALTER VIEW vwEmployeesEngineering

WITH SCHEMABINDING

SELECT FirstName, LastName, AdditionalColumn

FROM dbo.Employees

WHERE Department = 'Engineering'

-- 008

EXEC sp_refreshview 'vwEmployeesEngineering'

-- 009

CREATE OR ALTER VIEW vwEmployeesEngineering

WITH ENCRYPTION

SELECT FirstName, LastName, AdditionalColumn

FROM dbo.Employees

WHERE Department = 'Engineering'

-- 010

SELECT object_name(id), text

FROM sys.syscomments

-- 011

UPDATE vwEmployeesEngineering

SET FirstName = 'Bobby'

WHERE FirstName = 'Bob'

-- 012

UPDATE vwEmployeesEngineering

SET Department = 'Sales'

WHERE FirstName = 'Bobby'

-- 013

UPDATE dbo.Employees

SET FirstName = 'Bob', Department = 'Engineering'

WHERE FirstName = 'Bobby'

CREATE OR ALTER VIEW vwEmployeesEngineering

SELECT *

FROM dbo.Employees

WHERE Department = 'Engineering'

WITH CHECK OPTION

-- 014

INSERT INTO [dbo].[vwEmployeesEngineering]

([FirstName], [LastName], [Address], [Salary], [Department])

VALUES ('James' ,'Jameson' ,'Somewhere in Ireland' ,1000 ,'sales')

-- 015

DELETE FROM vwEmployeesEngineering WHERE FirstName = 'James'

-- 016

DROP VIEW IF EXISTS vwEmployeesEngineering

/* Implement input and output parameters in stored procedures */

-- 017

CREATE OR ALTER PROC procGetEmployeeInformation

BEGIN

--explanation of what the stored proc does

SET NOCOUNT ON;

SELECT *

FROM Employees;

END

-- 018

EXEC procGetEmployeeInformation

-- 019

DROP PROC IF EXISTS procGetEmployeeInformation

-- 020

CREATE PROC procGetEmployeeID

@FirstName varchar(100)

,@LastName varchar(50)

,@Address varchar(100)

BEGIN

SELECT EmployeeID

FROM Employees

WHERE FirstName = @FirstName

AND LastName = @LastName

AND Address = @Address;

END;

-- 021

EXEC procGetEmployeeID @FirstName = 'Bob', @LastName = 'Jackson', @Address = 'Under the bridge'

EXEC procGetEmployeeID 'Bob', 'Jackson', 'Under the bridge'

-- 022

CREATE OR ALTER PROC procGetEmployeeID

@FirstName varchar(100)

,@LastName varchar(50)

,@Address varchar(100)

,@EmployeeID tinyint OUTPUT

BEGIN

SELECT @EmployeeID = EmployeeID

FROM Employees

WHERE FirstName = @FirstName

AND LastName = @LastName

AND Address = @Address;

END;

-- 023

DECLARE @EmployeeID tinyint

EXEC procGetEmployeeID 'Bob', 'Jackson', 'Under the bridge', @EmployeeID = @EmployeeID OUTPUT

SELECT @EmployeeID

-- 024

CREATE PROC procLogicalTest

@parameter int

BEGIN

IF @parameter = 1

BEGIN

EXEC proc1;

END

ELSE

BEGIN

EXEC proc2

END

END;

/* functions */

-- 025

CREATE FUNCTION dbo.fn_rand ()

RETURNS INT

BEGIN

RETURN RAND()

END

-- 026

CREATE OR ALTER FUNCTION dbo.fn_doubler (@a int)

RETURNS INT

BEGIN

RETURN @a * 2

END

-- 027

SELECT dbo.fn_doubler (18)

-- 028

SELECT FirstName

, LastName

, dbo.fn_doubler(salary) as TwiceTheSalary

FROM dbo.Employees

-- 029

CREATE FUNCTION dbo.fn_GetListOfEmployees(@Department AS varchar(100))

RETURNS TABLE

RETURN

(

SELECT FirstName + ' ' + LastName AS FullName, Salary

FROM Employees e

WHERE e.Department = @Department

)

-- 030

SELECT * FROM dbo.fn_GetListOfEmployees('Sales')

-- 031

CREATE OR ALTER FUNCTION dbo.fn_name (...)

RETURNS @return_table TABLE

BEGIN

--some statements

--a statement to fill the table variable

INSERT @return_table

SELECT ...

--return the table variable to the calling statement

RETURN

END

-- 032

CREATE dbo.ManagersAllTheWayToTheTop (@employeeid tinyint)

RETURNS @tbl_managers TABLE

(

Name varchar(151)

, Manager varchar(151)

,Level tinyint

)

BEGIN

WITH Employee_CTE AS (

SELECT EmployeeID, ManagerID, 0 as Level

FROM Employees

WHERE FirstName = 'Bob'

UNION ALL

SELECT e1.EmployeeID, e1.ManagerID, e2.level + 1

FROM Employees e1

INNER JOIN Employee_CTE e2 ON e1.EmployeeID = e2.ManagerID

)

Distinct_CTE AS (

SELECT DISTINCT EmployeeID, ManagerID, Level

FROM Employee_CTE)

INSERT INTO @tbl_managers

SELECT e2.FirstName + ' ' + e2.LastName AS Name

, e3.FirstName + ' ' + e3.LastName AS Manager, Level

FROM Distinct_CTE e1

INNER JOIN Employees e2 ON e1.employeeID = e2.EmployeeID

LEFT OUTER JOIN Employees e3 ON e1.ManagerID = e3.EmployeeID

ORDER BY Level, Name

RETURN

END

SELECT * FROM dbo.managersallthewaytothetop(1)

DROP FUNCTION IF EXISTS dbo.ManagersAllTheWayToTheTop

-- 033

CREATE OR ALTER FUNCTION dbo.fn_doubler (@a int)

RETURNS INT

BEGIN

RETURN @a * 2

END

SELECT OBJECTPROPERTYEX(OBJECT_ID('dbo.fn_doubler'), 'IsDeterministic')

-- 034

CREATE OR ALTER FUNCTION dbo.fn_doubler (@a int)

RETURNS INT

WITH SCHEMABINDING

BEGIN

RETURN @a * 2

END

SELECT OBJECTPROPERTYEX(OBJECT_ID('dbo.fn_doubler'), 'IsDeterministic')

/* Implement error handling and transactions */

--For more information on isolation levels, see: https://docs.microsoft.com/en-us/sql/connect/jdbc/understanding-isolation-levels?view=sql-server-2016

-- 035

USE TestDB

DROP TABLE IF EXISTS dbo.OrderLines

DROP TABLE IF EXISTS dbo.Orders

DROP TABLE IF EXISTS dbo.Customers

CREATE TABLE dbo.Customers(

CustomerID int IDENTITY(1,1) NOT NULL,

FirstName varchar(100) NOT NULL,

LastName varchar(100) NOT NULL,

[Address] varchar(100) NOT NULL,

PRIMARY KEY CLUSTERED (CustomerID)

)

CREATE TABLE dbo.Orders(

OrderID int IDENTITY(1,1) NOT NULL,

CustomerID int NOT NULL,

OrderDate datetime NOT NULL,

SalesAmount money NOT NULL,

PRIMARY KEY CLUSTERED (OrderID )

)

CREATE TABLE dbo.OrderLines(

OrderID int NOT NULL,

OrderLineID int IDENTITY(1,1) NOT NULL,

Item varchar(100) NOT NULL,

Amount int NOT NULL,

LineAmount money NOT NULL,

PRIMARY KEY CLUSTERED (OrderID, OrderLineID )

)

ALTER TABLE dbo.Orders ADD CONSTRAINT FK_customerID

FOREIGN KEY (CustomerID) REFERENCES dbo.Customers(CustomerID)

ALTER TABLE dbo.OrderLines ADD CONSTRAINT FK_OrderID

FOREIGN KEY (OrderID) REFERENCES dbo.Orders(OrderID)

-- 036

INSERT dbo.Customers VALUES ('Bob', 'Jackson', 'Main street 1, Dallas')

-- 037

SET IMPLICIT_TRANSACTIONS ON

INSERT dbo.Customers VALUES ('Frank', 'Smith', 'Second street 2, Miami')

-- 038

SELECT *

FROM Customers

-- 039

SELECT *

FROM Customers WITH (NOLOCK)

-- 040

DBCC OPENTRAN();

-- 041

SELECT session_id, open_transaction_count

FROM sys.dm_exec_sessions

WHERE session_id > 50;

-- 042

SELECT @@TRANCOUNT

-- 043

COMMIT TRANSACTION

-- 044

SET IMPLICIT_TRANSACTIONS OFF

-- 045

BEGIN TRANSACTION

INSERT dbo.Customers VALUES ('Joe', 'Johnson', 'Third Avenue 3, New York')

COMMIT TRANSACTION

-- 046

BEGIN TRAN MyTran WITH MARK 'StartOfTransaction'

-- 047

ROLLBACK

/* Nesting transactions */

-- 048

INSERT Orders (CustomerID, OrderDate, SalesAmount)

VALUES (1, GETDATE(), 10.00)

-- 049

UPDATE Orders SET SalesAmount = 10.00

BEGIN TRAN

SELECT @@Trancount AS 'Transaction level'

UPDATE Orders

SET SalesAmount = SalesAmount + 1

WHERE orderid = 1

BEGIN TRAN

SELECT @@Trancount AS 'Transaction level'

UPDATE Orders

SET SalesAmount = SalesAmount + 1

WHERE orderid = 1

BEGIN TRAN

SELECT @@Trancount AS 'Transaction level'

UPDATE Orders

SET SalesAmount = SalesAmount + 1

WHERE orderid = 1

COMMIT TRAN

SELECT @@Trancount AS 'Transaction level'

COMMIT TRAN

SELECT @@Trancount AS 'Transaction level'

COMMIT TRAN

SELECT *

FROM Orders

WHERE orderid = 1

-- 050

UPDATE Orders SET SalesAmount = 10.00

BEGIN TRAN

SELECT @@Trancount AS 'Transaction level'

UPDATE Orders

SET SalesAmount = SalesAmount + 1

WHERE orderid = 1

BEGIN TRAN

SELECT @@Trancount AS 'Transaction level'

UPDATE Orders

SET SalesAmount = SalesAmount + 1

WHERE orderid = 1

BEGIN TRAN

SELECT @@Trancount AS 'Transaction level'

UPDATE Orders

SET SalesAmount = SalesAmount + 1

WHERE orderid = 1

COMMIT TRAN

SELECT @@Trancount AS 'Transaction level'

ROLLBACK TRAN --<<<< Only this line has changed

SELECT @@Trancount AS 'Transaction level'

COMMIT TRAN

SELECT *

FROM Orders

WHERE orderid = 1

/* Named transaction */

-- 051

UPDATE Orders SET SalesAmount = 10.00

BEGIN TRAN MyFirstTransaction

SELECT @@Trancount AS 'Transaction level'

UPDATE Orders

SET SalesAmount = SalesAmount + 1

WHERE orderid = 1

BEGIN TRAN MySecondTransaction

SELECT @@Trancount AS 'Transaction level'

UPDATE Orders

SET SalesAmount = SalesAmount + 1

WHERE orderid = 1

BEGIN TRAN MyThirdTransaction

SELECT @@Trancount AS 'Transaction level'

UPDATE Orders

SET SalesAmount = SalesAmount + 1

WHERE orderid = 1

COMMIT TRAN MyThirdTransaction

SELECT @@Trancount AS 'Transaction level'

ROLLBACK TRAN MySecondTransaction

SELECT @@Trancount AS 'Transaction level'

COMMIT TRAN MyFirstTransaction

SELECT *

FROM Orders

WHERE orderid = 1

-- 052

ROLLBACK TRAN

/* savepoints */

-- 053

UPDATE Orders SET SalesAmount = 10.00

BEGIN TRAN

UPDATE Orders

SET SalesAmount = SalesAmount + 1

WHERE orderid = 1

UPDATE Orders

SET SalesAmount = SalesAmount + 1

WHERE orderid = 1

SAVE TRANSACTION MyFirstSavepoint

UPDATE Orders

SET SalesAmount = SalesAmount + 1

WHERE orderid = 1

ROLLBACK TRANSACTION MyFirstSavepoint

COMMIT TRAN

SELECT *

FROM Orders

WHERE orderid = 1

-- what is rolled back?

-- 054

EXEC xp_cmdshell 'mkdir d:\Test_directory'

-- 055

BEGIN TRAN

EXEC xp_cmdshell 'mkdir d:\Test_directory'

ROLLBACK

-- 056

BEGIN TRAN

CREATE DATABASE TooBad

ROLLBACK

-- 057

SET NOCOUNT ON

DECLARE @MyToughVariable INT

SET @MyToughVariable = 1

SELECT IDENT_CURRENT('Customers') AS 'Current identity'

BEGIN TRAN

SET @MyToughVariable = 2

SELECT @MyToughVariable AS 'Variable'

CREATE TABLE MysteryTable (MysterID INT IDENTITY, Mystery VARCHAR(100))

INSERT MysteryTable VALUES ('Who killed Kennedy?')

SELECT *

FROM MysteryTable

ALTER TABLE dbo.Customers ADD DateOfBirth DATETIME NULL

INSERT dbo.Customers

VALUES ('Serena', 'Baker', 'Broadway, New York', GETDATE())

SELECT * FROM Customers

ROLLBACK TRAN

SELECT @MyToughVariable AS 'Variable'

SELECT IDENT_CURRENT('Customers') AS 'Current identity'

SELECT *

FROM dbo.Customers

SELECT *

FROM MysteryTable

-- 058

SET XACT_ABORT ON

-- 059

DROP TABLE IF EXISTS MysteryTable;

-- application timeout example

-- 060

USE TestDB

SET XACT_ABORT ON

BEGIN TRAN

CREATE TABLE MysteryTable (MysterID INT IDENTITY, Mystery VARCHAR(100))

INSERT MysteryTable VALUES ('Who killed Kennedy?')

WAITFOR DELAY '00:01'

COMMIT TRAN

-- 061

SELECT * FROM MysteryTable;

/* foreign key error example */

-- 062

SET XACT_ABORT ON

BEGIN TRAN

DECLARE @Order_id INT

INSERT Orders (CustomerID, OrderDate, SalesAmount)

VALUES (2, GETDATE(), 50.00)

SET @Order_id = @@IDENTITY

INSERT OrderLines (OrderID, Item, Amount, LineAmount)

VALUES (@Order_id , 'Bag of screws', 4, 10.00)

INSERT OrderLines (OrderID, Item, Amount, LineAmount)

VALUES (@Order_id + 1, 'Screwdriver', 1, 10.00)

COMMIT

/* Implement TRY…CATCH error handling with Transact-SQL */

-- 063

BEGIN TRY

DECLARE @MyVariable INT

SET @MyVariable = 5

SET @MyVariable = @MyVariable/0

PRINT 'This line of code will not be executed'

END TRY

BEGIN CATCH

PRINT 'A useful error message'

END CATCH

-- 064

BEGIN TRY

DECLARE @MyVariable INT;

SET @MyVariable = 5;

SET @MyVariable = @MyVariable/0;

PRINT 'This line of code will not be executed';

END TRY

BEGIN CATCH

SELECT

ERROR_NUMBER() AS ErrorNumber,

ERROR_SEVERITY() AS ErrorSeverity,

ERROR_STATE() AS ErrorState,

ISNULL(ERROR_PROCEDURE(), 'Not inside a stored proc') AS ErrorProcedure,

ERROR_LINE() AS ErrorLine,

ERROR_MESSAGE() AS ErrorMessage;

END CATCH

/* THROW */

-- 065

BEGIN TRY

DECLARE @MyVariable INT;

SET @MyVariable = 5;

SET @MyVariable = @MyVariable/0;

PRINT 'This line of code will not be executed';

END TRY

BEGIN CATCH

PRINT 'A useful error message';

THROW;

PRINT 'This line of code will not be executed either';

END CATCH ;

-- 066

THROW 50000, 'A useful error message', 0;

-- 067

DECLARE @msg_number INT = 50000

,@msg_text NVARCHAR(2048) = N'A useful error message'

,@msg_state TINYINT = 0;

THROW @msg_number, @msg_text, @msg_state;

-- 068

SET @msg_text = 'This error occurred on '

+ CONVERT(varchar(19),getdate(), 20) + ', process id '

+ CONVERT(varchar(10),@@SPID);

-- 069

USE master;

EXEC sp_addmessage @msgnum = 50001

,@severity = 16

,@msgtext = 'This error occurred on %s , process id %s.'

,@lang = 'us_english';

EXEC sp_addmessage @msgnum = 50001

,@severity = 16

,@msgtext = 'Dieser Fehler ist aufgetreten %1!,Prozess ID %2!'

,@lang = 'German';

-- 070

DECLARE @msg_number INT = 50001

,@msg_text NVARCHAR(2048)

,@msg_state TINYINT = 0;

SET LANGUAGE German;

SET @msg_text = FORMATMESSAGE(50001, CONVERT(varchar(19),getdate(), 20), CONVERT(varchar(10),@@SPID));

THROW @msg_number, @msg_text, @msg_state;

-- 071

DECLARE @msg_number INT = 50001

,@msg_text NVARCHAR(2048)

,@msg_state TINYINT = 0;

SET LANGUAGE us_english;

SET @msg_text = FORMATMESSAGE(50001, CONVERT(varchar(19),getdate(), 20), CONVERT(varchar(10),@@SPID));

THROW @msg_number, @msg_text, @msg_state;

/* RAISERROR */

-- 072

DECLARE @date varchar(19) = CONVERT(varchar(19),getdate(), 20)

,@process_id varchar(10) = CONVERT(varchar(10),@@SPID);

RAISERROR (50001, 16, 1, @date, @process_id);

DECLARE @date varchar(19) = CONVERT(varchar(19),getdate(), 20)

,@process_id varchar(10) = CONVERT(varchar(10),@@SPID);

RAISERROR ('This error occurred on %s , process id %s.', 16, 1, @date, @process_id);

DECLARE @date varchar(19) = CONVERT(varchar(19),getdate(), 20)

,@process_id varchar(10) = CONVERT(varchar(10),@@SPID)

,@msg_text nvarchar (100) = N'This error occurred on %s , process id %s.';

RAISERROR (@msg_text, 16, 1, @date, @process_id);

-- 073

DECLARE @date varchar(19) = CONVERT(varchar(19),getdate(), 20)

,@process_id varchar(10) = CONVERT(varchar(10),@@SPID)

,@msg_text nvarchar (100) = N'This error occurred on %s , process id %s.';

RAISERROR (@msg_text, 20, 1, @date, @process_id) WITH LOG;

-- 074

EXEC sp_dropmessage @msgnum = 50001, @lang = 'all';

-- 075

DROP TABLE IF EXISTS MysteryTable;

DECLARE @date varchar(19) = CONVERT(varchar(19),getdate(), 20)

,@process_id varchar(10) = CONVERT(varchar(10),@@SPID);

SET XACT_ABORT OFF;

BEGIN TRAN

CREATE TABLE MysteryTable (MysterID INT IDENTITY, Mystery VARCHAR(100));

INSERT MysteryTable VALUES ('Who killed Kennedy?');

THROW 50000, 'A useful error message', 0;

--RAISERROR (50001, 16, 1, @date, @process_id);

COMMIT

SELECT * FROM MysteryTable;

/* Implement transaction control in conjunction with error handling in stored procedures */

-- 076

CREATE PROCEDURE usp_my_stored_proc @MyVariable <data_type>

BEGIN

SET XACT_ABORT, NOCOUNT ON;

BEGIN TRY

BEGIN TRAN

--Validate input parameter(s)

IF @MyVariable ...

--Actual work

...

COMMIT TRAN

END TRY

BEGIN CATCH

IF @@TRANCOUNT > 0 ROLLBACK TRAN

-- error message, either THROW, RAISERROR or custom error logging code

END CATCH

END

-- 077

CREATE PROC usp_inner_proc

BEGIN

SET XACT_ABORT ON

BEGIN TRY

BEGIN TRAN

SELECT 5/0

COMMIT TRAN

END TRY

BEGIN CATCH

ROLLBACK;

THROW

END CATCH

END

CREATE PROC usp_outer_proc

BEGIN

SET XACT_ABORT ON

BEGIN TRY

BEGIN TRAN

EXEC usp_inner_proc

COMMIT TRAN

END TRY

BEGIN CATCH

ROLLBACK;

THROW

END CATCH

END

EXEC usp_outer_proc

-- 078

ALTER PROC usp_outer_proc

BEGIN

SET XACT_ABORT ON

BEGIN TRY

BEGIN TRAN

EXEC usp_inner_proc

COMMIT TRAN

END TRY

BEGIN CATCH

IF @@TRANCOUNT > 0 ROLLBACK;

THROW

END CATCH

END

-- 079

DROP PROC IF EXISTS usp_inner_proc

DROP PROC IF EXISTS usp_outer_proc

--For more information about error handling, read the eBook Defensive Database Programming with SQL Server, by Alex Kuznetsov, available for free at: https://www.red-gate.com/library/defensive-database-programming

/* Implement data types and NULLs */

DECLARE @MyVariable DECIMAL(5,2)

DECLARE @MyVariable FLOAT(n)

-- 080

DECLARE @MyVariable real = 100.123456789

SELECT STR(@MyVariable, 6,2)

--text

DECLARE @MyVariable CHAR(4) = 'Text'

DECLARE @MyVariable NCHAR(4) = N'Text'

-- 081

DECLARE @MyVariable uniqueidentifier = NEWID()

SELECT @MyVariable

--rowversion

-- 082

CREATE TABLE Table1 (Column1 smallint, Column2 rowversion)

INSERT Table1 (Column1) VALUES (1)

SELECT * FROM Table1

UPDATE Table1 SET Column1 = 2

SELECT * FROM Table1

--implicit conversion

-- 083

DECLARE @MyVariable INT = '45'

SET @MyVariable = @MyVariable + 10

IF @MyVariable > '50'

PRINT 'Yep, it''s bigger.'

-- 084

DECLARE @MyVariable VARCHAR(100) = 'My favourite number is '

SET @MyVariable = @MyVariable + 16

SELECT @MyVariable

-- The complete data type precedence list: https://docs.microsoft.com/en-us/sql/t-sql/data-types/data-type-precedence-transact-sql?view=sql-server-2016

-- Implicit conversions: https://docs.microsoft.com/en-us/sql/t-sql/data-types/data-type-conversion-database-engine?view=sql-server-2016

-- 085

SELECT 2/5

SELECT 2000000000 + 2000000000

-- 086

SELECT 2000000000 + 4000000000

-- 087

DECLARE @MyVariable numeric(3,2) = 4.63

SELECT @MyVariable AS column1

INTO Type_check_table

/* ISNULL versus COALESCE */

-- 088

DECLARE @MyNULLVariable VARCHAR(100)

,@MyNonNULLVariable VARCHAR(100) = 'Original value'

SELECT ISNULL(@MyNULLVariable, 'Replacement value')

,ISNULL(@MyNonNULLVariable, 'Replacement value')

-- 089

DECLARE @MyNULLVariable VARCHAR(100)

,@MyNonNULLVariable VARCHAR(100) = 'Original value'

SELECT COALESCE(@MyNULLVariable, @MyNonNULLVariable, 'Replacement value')

-- 090

SELECT CASE

WHEN @MyNULLVariable IS NOT NULL THEN @MyNULLVariable

WHEN @MyNonNULLVariable IS NOT NULL THEN @MyNonNULLVariable

ELSE 'Replacement value'

END

-- 091

DECLARE @MyDateVariable date = '2018-10-05'

,@MyDateTimeVariable datetime = '2018-10-05 11:07'

SELECT ISNULL(@MyDateVariable, @MyDateTimeVariable)

, COALESCE(@MyDateVariable, @MyDateTimeVariable)

-- 092

DROP TABLE IF EXISTS Type_check_table

DECLARE @MyDateVariable date = '2018-10-05'

SELECT ISNULL(@MyDateVariable, '2018-10-05 11:07') AS column1

,ISNULL('2018-10-05 11:07', @MyDateVariable) AS column2

,ISNULL(@MyDateVariable, @MyDateVariable) AS column3

,ISNULL('2018-10-05 11:07', '2018-10-05 11:07') AS column4

INTO Type_check_table

SELECT c.name, t.name, c.max_length, c.precision, c.scale, c.is_nullable

FROM sys.columns c

INNER JOIN sys.types t ON c.system_type_id = t.system_type_id

WHERE object_id = object_id('Type_check_table')

DROP TABLE IF EXISTS Type_check_table

-- 093

SELECT *

INTO Customers_copy

FROM WideWorldImporters.sales.Customers

SELECT *

INTO orders_copy

FROM WideWorldImporters.sales.orders

-- 094

SELECT CustomerName

,ISNULL(( SELECT MAX(OrderDate)

FROM Orders_copy o

WHERE o.CustomerID = c.CustomerID), '1900-1-1')

FROM Customers_copy c

SELECT CustomerName

,COALESCE(( SELECT MAX(OrderDate)

FROM Orders_copy o

WHERE o.CustomerID = c.CustomerID), '1900-1-1')

FROM Customers_copy c

-- 095

SELECT CustomerName

,CASE WHEN ( SELECT MAX(OrderDate)

FROM Orders_copy o

WHERE o.CustomerID = c.CustomerID) IS NOT NULL

THEN (

SELECT MAX(OrderDate)

FROM Orders_copy o

WHERE o.CustomerID = c.CustomerID)

ELSE '1900-1-1'

END

FROM Customers_copy c

Code samples for my book on Querying data with Transact-SQL (MCSA 70-761), chapter 2

Posted on September 8, 2018 by Robert

USE WideWorldImporters;

/* Query data by using subqueries and APPLY */

-- 001
-- simple subquery
SELECT	o.*
FROM	(SELECT * FROM Sales.Orders) o

-- 002
SELECT	*
FROM	[Application].[People]
WHERE	PreferredName IN (	SELECT	CustomerName
				FROM	sales.Customers )

-- 003
USE TestDB;

SELECT	*
	,(SELECT AVG(salary) FROM dbo.Employees) AS average_salary
FROM	dbo.Employees

-- 004
SELECT	*
FROM	dbo.Employees
WHERE	Salary > (SELECT AVG(salary) FROM dbo.Employees)

-- 005
-- correlated subquery
SELECT	*
FROM	dbo.Employees e1
WHERE	Salary > (	SELECT	AVG(salary) 
					FROM	Employees e2 
					WHERE	e1.department = e2.department)

-- 006
SELECT	*
FROM	dbo.Employees e1
	INNER JOIN (SELECT	AVG(salary) AS avg_salary, department
		    FROM	dbo.employees
		    GROUP BY department) e2 ON e1.Department = e2.Department
WHERE	salary > e2.avg_salary

-- 007
SELECT	*
	, (SELECT AVG(salary) FROM Employees e2 WHERE e1.department = e2.Department)
FROM	Employees e1
WHERE	Salary > (	SELECT	AVG(salary) 
			FROM	Employees e2 
			WHERE	e1.Department = e2.department)

-- 008
SELECT	*
FROM	Departments d
WHERE (	SELECT	count (*)
	FROM	Employees e 
	WHERE	e.Department = d.Department) > 2 

-- 009
ALTER TABLE Departments ADD Location varchar(100) DEFAULT 'Houston' WITH VALUES;
GO
UPDATE Departments
SET 	Location = 'New York'
WHERE 	Department = 'Management'


/* Evaluate performance differences between table joins and correlated subqueries based on provided data and query plans */

-- 010
SELECT	*
INTO	Customers_copy
FROM	WideWorldImporters.sales.Customers

SELECT	*
INTO	orders_copy
FROM	WideWorldImporters.sales.orders

-- 011
-- join faster
SELECT	c.CustomerName, o.lastorderdate, o.NumberOfOrders
FROM	(SELECT customerID, max(orderdate) AS LastOrderDate, count(*) AS NumberOfOrders
	FROM	orders_copy
	GROUP BY CustomerID) o
	INNER JOIN Customers_copy c on c.CustomerID = o.customerId

SELECT CustomerName
	,(	SELECT MAX(orderdate) 
		FROM orders_copy o 
		WHERE c.customerId = o.customerID ) AS LastOrderDate
	,(	SELECT COUNT(*) 
		FROM orders_copy o 
		WHERE c.customerId = o.customerID )AS NumberOfOrders
FROM	Customers_copy c

-- 012
-- correlated subquery faster
SELECT	*
FROM	Customers_copy c
	LEFT OUTER JOIN orders_copy o on c.CustomerID = o.CustomerID
WHERE	o.CustomerID IS NULL

SELECT	*
FROM	Customers_copy c
WHERE NOT EXISTS (	SELECT	* 
			FROM	orders_copy o 
			WHERE	c.CustomerID = o.CustomerID)

/* Distinguish between the use of CROSS APPLY and OUTER APPLY */

-- 013
SELECT	* 
FROM	Departments d
	CROSS APPLY 
	(	SELECT * 
FROM 	Employees e 
		WHERE 	e.Department = d.Department) table_alias

SELECT	* 
FROM	Departments d
	INNER JOIN Employees e ON d.Department = e.Department

-- 014
INSERT Departments VALUES ('Research', 'Eindhoven')

SELECT	* 
FROM	Departments d
	OUTER APPLY 
	(	SELECT * 
FROM 	Employees e 
		WHERE 	e.Department = d.Department) table_alias

SELECT	* 
FROM	Departments d
	LEFT OUTER JOIN Employees e ON d.Department = e.Department

-- 015
CREATE FUNCTION dbo.fn_GetListOfEmployees(@Department AS varchar(100))  
RETURNS TABLE 
AS 
RETURN 
   ( 
   SELECT	FirstName + ' ' + LastName AS FullName, Salary
   FROM	Employees e 
   WHERE	e.Department = @Department 
   ) 

-- 016
SELECT	*
FROM	dbo.fn_GetListOfEmployees('Engineering')

-- 017
SELECT	*
FROM	Departments d
	CROSS APPLY dbo.fn_GetListOfEmployees(d.Department)

-- 018
SELECT	session_id, DB_NAME(database_id) AS [database], start_time
		, open_transaction_count,  [text] AS [Query] 
FROM	sys.dm_exec_requests r 
	CROSS APPLY sys.dm_exec_sql_text(r.plan_handle) s 
WHERE	session_id > 50           -- Exclude system spids
ORDER BY session_id;

/* Query data by using table expressions */


--Identify basic components of table expressions
SELECT	o.*
FROM	(SELECT * FROM Sales.Orders) o

-- common table expression
WITH o 
AS (	SELECT * 
	FROM Sales.Orders)
SELECT	*
FROM	o


SELECT	*
FROM	dbo.Employees e1
WHERE	Salary > (	SELECT	AVG(salary) 
					FROM	Employees e2 
					WHERE	e1.Department = e2.department);

-- readability example
SELECT	c.CustomerName, o.lastorderdate, o.NumberOfOrders
FROM	(SELECT customerID, max(orderdate) AS LastOrderDate, count(*) AS NumberOfOrders
		FROM	orders_copy
		GROUP BY CustomerID) o
		INNER JOIN Customers_copy c on c.CustomerID = o.customerId;


WITH o AS (
	SELECT customerID, max(orderdate) AS LastOrderDate, count(*) AS NumberOfOrders
	FROM	orders_copy
	GROUP BY CustomerID)
SELECT	c.CustomerName, o.lastorderdate, o.NumberOfOrders
FROM	o
		INNER JOIN Customers_copy c on c.CustomerID = o.customerId

--Construct recursive table expressions to meet business requirements


-- Recursive cte, top to bottom:
ALTER TABLE Employees ADD ManagerID tinyint NULL;
GO
INSERT Employees (FirstName,LastName, Salary, Department, ManagerID)
VALUES ('Harriet', 'Hughes', 1800.00,'Sales',7);
INSERT Employees (FirstName,LastName, Salary, Department, ManagerID)
VALUES ('Ronnie', 'Robertson', 1800.00,'Engineering',7);

UPDATE	Employees 
SET		ManagerID = (SELECT EmployeeID FROM Employees WHERE FirstName = 'Harriet')
WHERE	Department = 'Sales' AND FirstName <> 'Harriet'

UPDATE	Employees 
SET		ManagerID = (SELECT EmployeeID FROM Employees WHERE FirstName = 'Ronnie')
WHERE	Department = 'Engineering' AND FirstName <> 'Ronnie'

ALTER TABLE Employees ADD CONSTRAINT PK_EmployeeID PRIMARY KEY (EmployeeID)

ALTER TABLE Employees ADD CONSTRAINT FK_EmployeeID FOREIGN KEY (ManagerID) REFERENCES Employees(EmployeeID)
GO

WITH Employee_CTE AS (
	SELECT	EmployeeID,  ManagerID, Firstname + ' ' + LastName AS Name, 0 as Level
	FROM	Employees
	WHERE	ManagerID IS NULL
	UNION ALL
	SELECT	e1.EmployeeID, e1.ManagerID, Firstname + ' ' + LastName, e2.level + 1
	FROM	Employees e1
			INNER JOIN Employee_CTE e2 ON e2.EmployeeID = e1.ManagerID
)
SELECT	Name,  Level
FROM	Employee_CTE
ORDER BY  Level, Name

-- Recursive cte, bottom to top:
WITH Employee_CTE AS (
	SELECT	EmployeeID,  ManagerID, Firstname + ' ' + LastName AS Name, 0 as Level
	FROM	Employees
	WHERE	EmployeeID NOT IN (SELECT ManagerID FROM Employees WHERE ManagerID IS NOT NULL)
	UNION ALL
	SELECT	e1.EmployeeID, e1.ManagerID, Firstname + ' ' + LastName, e2.level + 1
	FROM	Employees e1
			INNER JOIN Employee_CTE e2 ON e1.EmployeeID = e2.ManagerID
)
SELECT	DISTINCT Name,  Level
FROM	Employee_CTE
ORDER BY  Level, Name


-- Recursive CTE, final example
WITH Employee_CTE AS (
	SELECT	EmployeeID, ManagerID, 0 as Level
	FROM	Employees
	WHERE	EmployeeID NOT IN (SELECT ManagerID FROM Employees WHERE ManagerID IS NOT NULL)
	UNION ALL
	SELECT	e1.EmployeeID, e1.ManagerID, e2.level + 1
	FROM	Employees e1
			INNER JOIN Employee_CTE e2 ON e1.EmployeeID = e2.ManagerID
)
,
Distinct_CTE AS (
	SELECT DISTINCT EmployeeID,  ManagerID, Level
	FROM Employee_CTE)
SELECT	e2.FirstName + ' ' + e2.LastName AS Name, e3.FirstName + ' ' + e3.LastName AS Manager, Level
FROM	Distinct_CTE e1
		INNER JOIN Employees e2 ON e1.employeeID = e2.EmployeeID
		LEFT OUTER JOIN Employees e3 ON e1.ManagerID = e3.EmployeeID
ORDER BY Level, Name


--multiple CTEs
WITH Employee_CTE AS (
	SELECT	EmployeeID, ManagerID, 0 as Level
	FROM	Employees
	WHERE	EmployeeID NOT IN (	SELECT ManagerID 
FROM 	Employees 
WHERE 	ManagerID IS NOT NULL)
	UNION ALL
	SELECT	e1.EmployeeID, e1.ManagerID, e2.level + 1
	FROM	Employees e1
		INNER JOIN Employee_CTE e2 ON e1.EmployeeID = e2.ManagerID
)
,
Distinct_CTE AS (
	SELECT DISTINCT EmployeeID,  ManagerID, Level
	FROM Employee_CTE)
SELECT	e2.FirstName + ' ' + e2.LastName AS Name
, e3.FirstName + ' ' + e3.LastName AS Manager, Level
FROM	Distinct_CTE e1
	INNER JOIN Employees e2 ON e1.employeeID = e2.EmployeeID
	LEFT OUTER JOIN Employees e3 ON e1.ManagerID = e3.EmployeeID
ORDER BY Level, Name

--Temporary table
SELECT	*
INTO	#tmp_Employees
FROM	Employees

SELECT	*
FROM	#tmp_Employees

ALTER TABLE #tmp_Employees ADD Description varchar(100) NULL

DROP TABLE #tmp_Employees

SELECT	*
FROM	tempdb.sys.objects
WHERE	name LIKE '#tmp_Employees%'

--Table variables
DECLARE @Employees TABLE (
	[EmployeeID] [tinyint] NOT NULL,
	[FirstName] [varchar](100) NULL,
	[LastName] [varchar](50) NULL,
	[Address] [varchar](100) NULL,
	[Salary] [decimal](18, 2) NULL,
	[Department] [varchar](100) NULL,
	[Employee_Number] [int] NULL,
	[ManagerID] [tinyint] NULL)

INSERT INTO @Employees
SELECT	*
FROM	Employees

--Group and pivot data by using queries
--Construct complex GROUP BY clauses using GROUPING SETS, and CUBE

DROP TABLE IF EXISTS UFO_Sightings;
GO
CREATE TABLE UFO_Sightings (
CountryID tinyint
, Country varchar(50)
, State varchar(50)
, City varchar(50)
, UFO_Sightings int );

INSERT INTO UFO_Sightings VALUES (1, 'Germany', NULL, 'Berlin', 1)
INSERT INTO UFO_Sightings VALUES (1, 'Germany', NULL, 'Frankfurt', 2)
INSERT INTO UFO_Sightings VALUES (1, 'Germany', NULL, 'Frankfurt', 3)
INSERT INTO UFO_Sightings VALUES (2, 'United States', 'Texas', 'Houston', 1)
INSERT INTO UFO_Sightings VALUES (2, 'United States', 'Texas', 'Paris', 2)
INSERT INTO UFO_Sightings VALUES (2, 'United States', 'Nevada', NULL, 300)
INSERT INTO UFO_Sightings VALUES (3, 'France', NULL, 'Paris', 1);

SELECT	*
FROM	UFO_Sightings

SELECT	Country, SUM(UFO_Sightings)
FROM	UFO_Sightings
GROUP BY Country

SELECT	SUM(UFO_Sightings)
FROM	UFO_Sightings

SELECT	SUM(UFO_Sightings)
FROM	UFO_Sightings
GROUP BY ()

SELECT	Country, City, SUM(UFO_Sightings)
FROM	UFO_Sightings
GROUP BY Country, City
ORDER BY Country, City;

SELECT	Country, SUM(UFO_Sightings)
FROM	UFO_Sightings
WHERE	City <> 'Paris'
GROUP BY Country

SELECT	Country, SUM(UFO_Sightings)
FROM	UFO_Sightings
WHERE	ISNULL(City,'') <> 'Paris'
GROUP BY Country

SELECT	CountryID, Country, SUM(UFO_Sightings)
FROM	UFO_Sightings
GROUP BY Country

SELECT	Country, SUM(UFO_Sightings) AS TotalNumberOfSightings
FROM	UFO_Sightings
GROUP BY Country
HAVING	SUM(UFO_Sightings) > 100;

WITH ufo AS (
	SELECT	Country, SUM(UFO_Sightings) AS TotalNumberOfSightings
	FROM	UFO_Sightings
	GROUP BY Country)
SELECT	*
FROM	ufo
WHERE	TotalNumberOfSightings > 100

INSERT INTO UFO_Sightings VALUES (4, 'Belgium', NULL, 'Brussels', NULL);

SELECT Country, COUNT(UFO_Sightings) AS Count_1, COUNT(*) AS Count_2
FROM	UFO_Sightings
GROUP BY Country

SELECT Country, State, SUM(UFO_Sightings) AS TotalUFO_Sightings
FROM	UFO_Sightings
GROUP BY Country, State

--complex GROUP BY logic
SELECT Country, City, SUM(UFO_Sightings) AS TotalUFO_Sightings
FROM UFO_Sightings
GROUP BY Country, City
ORDER BY Country, City

SELECT Country, City, SUM(UFO_Sightings) AS TotalUFO_Sightings
FROM UFO_Sightings
GROUP BY ROLLUP (Country, City);

SELECT Country, NULL AS City, SUM(UFO_Sightings) AS TotalUFO_Sightings
FROM 	UFO_Sightings
GROUP BY Country 
UNION ALL
SELECT Country, City, SUM(UFO_Sightings) AS TotalUFO_Sightings
FROM 	UFO_Sightings
GROUP BY Country, City 
UNION ALL
SELECT NULL, NULL, SUM(UFO_Sightings) AS TotalUFO_Sightings
FROM 	UFO_Sightings
GROUP BY ()

GROUP BY Country, City WITH ROLLUP;

SELECT	Country, GROUPING(Country) AS Is_result_of_grouping_countries
	, State, GROUPING(State) AS Is_result_of_grouping_cities
FROM UFO_Sightings
GROUP BY Country, State WITH ROLLUP

SELECT	CASE 
		WHEN GROUPING(Country) = 1 THEN 'Grand Total' 
		WHEN GROUPING(State) = 1 THEN 'Total for ' + Country 
		ELSE ''
	END	AS Totals
	, Country
	, State
	,SUM(UFO_Sightings) AS TotalUFO_Sightings
FROM	UFO_Sightings
GROUP BY Country, State WITH ROLLUP

SELECT Country, State, GROUPING_ID(Country, State )
FROM UFO_Sightings
GROUP BY Country, State WITH ROLLUP

ALTER TABLE UFO_Sightings ADD Continent varchar(100) NULL

GO --required batch separator, otherwise query will fail on missing column

UPDATE UFO_Sightings 
SET 	Continent = 'Europe' 
WHERE 	Country IN ('Germany', 'France', 'Belgium')

UPDATE UFO_Sightings 
SET 	Continent = 'North America' 
WHERE 	Country IN ('United States')

SELECT	Continent
	, Country
	, State
	, GROUPING_ID(Continent, Country, State )
	, GROUPING(Continent) * 4 + GROUPING(Country) * 2 +  GROUPING(State)
FROM	UFO_Sightings
GROUP BY Continent, Country, State WITH ROLLUP

SELECT Country, City, SUM(UFO_Sightings) AS TotalUFO_Sightings
FROM UFO_Sightings
GROUP BY CUBE (Country, City)
ORDER BY 1, 2;

-- CUBE dissected: A & NULL, NULL & B, A & B, NULL & NULL
SELECT Country, NULL AS City, SUM(UFO_Sightings) AS TotalUFO_Sightings
FROM UFO_Sightings
GROUP BY (Country)
UNION ALL
SELECT NULL, City, SUM(UFO_Sightings) AS TotalUFO_Sightings
FROM UFO_Sightings
GROUP BY ( City)
UNION ALL
SELECT Country, City, SUM(UFO_Sightings) AS TotalUFO_Sightings
FROM UFO_Sightings
GROUP BY Country, City
UNION ALL
SELECT NULL, NULL, SUM(UFO_Sightings) AS TotalUFO_Sightings
FROM UFO_Sightings
ORDER BY 1, 2

SELECT Continent
, Country
, City
, SUM(UFO_Sightings) AS TotalUFO_Sightings
, GROUPING_ID(Continent,Country, City)
FROM UFO_Sightings
GROUP BY CUBE (Continent, Country, City)
ORDER BY 5;

SELECT	Country, City, SUM(UFO_Sightings) AS TotalUFO_Sightings
FROM	UFO_Sightings
GROUP BY GROUPING SETS ( Country, City)

SELECT	Country, NULL, SUM(UFO_Sightings) AS TotalUFO_Sightings
FROM	UFO_Sightings
GROUP BY  Country
UNION ALL
SELECT	NULL, City, SUM(UFO_Sightings) AS TotalUFO_Sightings
FROM	UFO_Sightings
GROUP BY  City

SELECT	Country, City, SUM(UFO_Sightings) AS TotalUFO_Sightings
FROM	UFO_Sightings
GROUP BY GROUPING SETS ( Country, City, ())

--Use windowing functions to group and rank the results of a query
DROP TABLE IF EXISTS Runner_info

CREATE TABLE Runner_info (
	Runner		varchar(50)
	,Nickname	varchar(50)
	,Race		varchar(50)
	,Race_date	date
	,Distance	decimal(8,3)
	,Finish_time	time)
GO
INSERT Runner_info VALUES ('Jack', 'The Flash', 'New York marathon', '2016-11-06', 42.195, '2:53:00')
INSERT Runner_info VALUES ('Jack', 'The Flash', 'New York marathon', '2017-11-05', 42.195, '2:55:00')
INSERT Runner_info VALUES ('Jack', 'The Flash', 'Berlin marathon', '2016-09-25', 42.195, '2:45:00')

INSERT Runner_info VALUES ('Juan Gonzalez', 'Speedy', 'New York marathon', '2016-11-06', 42.195, '3:22:00')
INSERT Runner_info VALUES ('Juan Gonzalez', 'Speedy', 'New York marathon', '2017-11-05', 42.195, '3:18:30')

INSERT Runner_info VALUES ('Rudy', 'Roadrunner', 'New York marathon', '2016-11-06', 42.195, '4:01:00')
INSERT Runner_info VALUES ('Rudy', 'Roadrunner', 'New York marathon', '2017-11-05', 42.195, '4:05:30')
INSERT Runner_info VALUES ('Rudy', 'Roadrunner', 'Berlin marathon', '2016-09-25', 42.195, '3:59:59')
INSERT Runner_info VALUES ('Rudy', 'Roadrunner', 'Berlin marathon', '2017-09-24', 42.195, '4:13:00')
INSERT Runner_info VALUES ('Rudy', 'Roadrunner', 'Rotterdam half marathon', '2017-04-07', 21.1, '1:52')

SELECT	*
FROM	Runner_info	

SELECT	*
	,COUNT(*) OVER () AS Nr_of_races_total
FROM	Runner_info	

SELECT	*
	,COUNT(*) OVER () AS Nr_of_races_total
	,COUNT(*) OVER (PARTITION BY Runner) AS Nr_of_races_per_runner
FROM	Runner_info	

SELECT	*
	,COUNT(*) OVER (PARTITION BY Runner) AS Nr_of_races_per_runner
FROM	Runner_info	
WHERE	Distance = 42.195

SELECT	Runner
	,Race
	,Race_date
	,Finish_time
	,MIN(Finish_time) OVER (PARTITION BY Runner, Race)  AS Race_PR
	,DATEDIFF(mi,MIN(Finish_time) OVER (PARTITION BY Runner, Race), Finish_time)  AS Slower_than_PR
FROM	Runner_info	

OVER (	PARTITION BY column
	ORDER BY column
	ROWS BETWEEN … AND …)

SELECT	Runner, Race, Race_date, distance
	,SUM(distance) OVER (PARTITION BY Runner 
				ORDER BY Race_date
				ROWS BETWEEN UNBOUNDED PRECEDING AND CURRENT ROW) 
AS Cumulative_distance
FROM	Runner_info	
WHERE	Runner = 'Rudy'
ORDER BY Runner, Race_date

SELECT	Runner, Race, Race_date, distance
	,AVG(distance) OVER (PARTITION BY Runner 
				ORDER BY Race_date
				ROWS BETWEEN 2 PRECEDING AND 2 FOLLOWING) 
AS Running_average
FROM	Runner_info	
WHERE	Runner = 'Rudy'
ORDER BY Runner, Race_date

INSERT Runner_info VALUES ('Rudy', 'Roadrunner', 'Ran home', '2017-11-05', 10, '1:10')

SELECT	Runner, Race, Race_date, distance
	,SUM(distance) OVER (PARTITION BY Runner 
				ORDER BY Race_date
				ROWS BETWEEN UNBOUNDED PRECEDING AND CURRENT ROW) 
AS Cumulative_distance
FROM	Runner_info	
WHERE	Runner = 'Rudy'
ORDER BY Runner, Race_date

SELECT	Runner, Race, Race_date, distance
	,SUM(distance) OVER (PARTITION BY Runner 
				ORDER BY Race_date
				RANGE BETWEEN UNBOUNDED PRECEDING AND CURRENT ROW) 
AS Cumulative_distance
FROM	Runner_info	
WHERE	Runner = 'Rudy'
ORDER BY Runner, Race_date

--Ranking window functions
SELECT	Runner, Race, Race_date, Finish_time
	,ROW_NUMBER() OVER (ORDER BY Finish_time) AS rownumber
	,RANK() OVER (ORDER BY Finish_time) AS rank
	,DENSE_RANK() OVER (ORDER BY Finish_time) AS denserank
	,NTILE(5) OVER (ORDER BY Finish_time) AS ntile
FROM	Runner_info
WHERE	Distance = 42.195
ORDER BY rownumber

INSERT Runner_info VALUES ('Fred', 'The Shadow', 'New York marathon', '2016-11-06', 42.195, '2:53:00')

--Analytic window functions
SELECT	FirstName, LastName, Department, Salary
FROM	dbo.Employees

SELECT	FirstName, LastName, Department, Salary
	,LAG(Salary) OVER (ORDER BY Salary) as lag
	,LEAD(Salary) OVER (ORDER BY Salary) as lead
FROM	Employees

SELECT	FirstName, LastName, Department, Salary
	,LAG(Salary) OVER (ORDER BY Salary) as lag
	,LEAD(Salary) OVER (ORDER BY Salary) as lead
FROM	Employees
ORDER BY LastName

SELECT	FirstName, LastName, Department, Salary
	,LAG(Salary, 2) OVER (ORDER BY Salary) as lag
	,LEAD(Salary, 2) OVER (ORDER BY Salary) as lead
FROM   Employees

SELECT	FirstName, LastName, Department, Salary
	,LAG(Salary, 2, 'not applicable') OVER (ORDER BY Salary) as lag
	,LEAD(Salary, 2, 'not applicable') OVER (ORDER BY Salary) as lead
FROM	Employees

SELECT	FirstName, LastName, Department, Salary
	,LAG(Salary) OVER (PARTITION BY Department ORDER BY Salary) as lag
	,LEAD(Salary) OVER (PARTITION BY Department ORDER BY Salary) as lead
FROM   Employees
ORDER BY Department

SELECT	FirstName, LastName, Department, Salary
	,FIRST_VALUE(FirstName + ' ' +  LastName) 
OVER (	PARTITION BY Department 
ORDER BY Salary) 
as Least_earning_employee
	,LAST_VALUE(FirstName + ' ' +  LastName) 
OVER (	PARTITION BY Department
ORDER BY Salary
			RANGE BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING) 
as Most_earning_employee
FROM   Employees
ORDER BY Department, Salary

SELECT	FirstName, LastName, Department, Salary
	,CUME_DIST() OVER (ORDER BY Salary) as cumulative_distance
	,CUME_DIST() OVER (ORDER BY Salary) * COUNT(*) OVER () as equal_or_less
FROM   Employees
ORDER BY Salary

INSERT dbo.Employees (FirstName, LastName, Salary, Department) 
VALUES ('James', 'Peterson', 900, 'Engineering')

SELECT	FirstName, LastName, Department, Salary
	,PERCENTILE_CONT(0.5) WITHIN GROUP (ORDER BY Salary) OVER () as median_salary
	,PERCENTILE_DISC(0.5) WITHIN GROUP (ORDER BY Salary) OVER () as median_salary
FROM   Employees
ORDER BY Salary

SELECT	FirstName, LastName, Department, Salary
	,PERCENT_RANK() OVER (ORDER BY Salary) as fraction_lower_than_this
	,CAST(PERCENT_RANK() OVER (ORDER BY Salary) * 100 AS dec(5,1)) 
as percentage_lower_than_this
FROM   Employees
ORDER BY Salary

--Construct PIVOT and UNPIVOT statements to return desired results based on supplied data
SELECT	CustomerName, si.StockItemName, sum(quantity) as quantity
FROM	sales.Customers c
	INNER JOIN sales.Orders o on c.CustomerID = o.CustomerID
	INNER JOIN sales.OrderLines ol on o.OrderID = ol.OrderID
	INNER JOIN Warehouse.StockItems si on ol.StockItemID = si.StockItemID
WHERE	c.CustomerID IN (	SELECT	TOP 5 CustomerID 
				FROM	Sales.Orders 
				GROUP BY CustomerID
				ORDER BY COUNT(*))
	AND si.StockItemID IN (	SELECT TOP 5 StockItemID 
					FROM Sales.Orderlines 
					GROUP BY StockItemID 
					ORDER BY COUNT(*))
GROUP BY CustomerName, si.StockItemName
ORDER BY CustomerName, si.StockItemName

--PIVOT and UNPIVOT
WITH cte AS(
	SELECT	CustomerName, si.StockItemName, quantity
	FROM	sales.Customers c
		INNER JOIN sales.Orders o on c.CustomerID = o.CustomerID
		INNER JOIN sales.OrderLines ol on o.OrderID = ol.OrderID
		INNER JOIN Warehouse.StockItems si on ol.StockItemID = si.StockItemID
	WHERE	si.StockItemID IN (	SELECT TOP 5 StockItemID 
					FROM Sales.Orderlines 
					GROUP BY StockItemID 
					ORDER BY COUNT(*))
)
SELECT	 *
FROM	cte
	PIVOT (SUM(quantity)
		FOR CustomerName IN ([Anand Mudaliyar],[Jibek Juniskyzy]
,[Agrita Abele],[Kalyani Benjaree],[Jaroslav Fisar])) 
		AS SalesQuantity

USE TestDB
GO
DROP TABLE IF EXISTS Sales;
GO
CREATE TABLE Sales(
	Customer	varchar(50)
	, Product	varchar(50)
	, Quantity	int)

INSERT INTO Sales(Customer, Product, Quantity)
VALUES('John','Apples',4)
,('John','Bananas',7)
,('John','Cantaloupe',1)
,('John','Apples',5)
,('John','Beer',6)
,('Bill','Cantaloupe',3)
,('Bill','Beer',24)
,('Diana','Apples',6)
,('Diana','Bananas',5)
,('Diana','Cantaloupe',2)

SELECT	*
FROM	Sales

-- Pivot customers
SELECT	Product, Bill, John, Diana
FROM	Sales
	PIVOT (SUM(Quantity) 
		FOR Customer IN (Bill, John, Diana)) AS some_alias
ORDER BY Product

-- Pivot product
SELECT	Customer, Apples, Bananas, Cantaloupe , Beer, [Magic mushrooms]
FROM	Sales
	PIVOT (SUM(Quantity) 
FOR Product IN (Apples, Bananas, Cantaloupe , Beer, [Magic mushrooms])) AS some_alias
ORDER BY Customer

-- adding a column
ALTER TABLE Sales ADD CustomerID int NULL
GO
UPDATE Sales SET CustomerID = 1 WHERE Customer = 'Bill'
UPDATE Sales SET CustomerID = 2 WHERE Customer = 'John'
UPDATE Sales SET CustomerID = 3 WHERE Customer = 'Diana'

SELECT	Product, Bill, John, Diana
FROM	Sales
	PIVOT (SUM(Quantity) 
		FOR Customer IN (Bill, John, Diana)) AS some_alias
ORDER BY Product

ALTER TABLE Sales DROP CustomerID

SELECT	Customer, Apples, Bananas, Cantaloupe , Beer, [Magic mushrooms]
INTO	Pivoted_sales_table
FROM	Sales
	PIVOT (SUM(Quantity) 
FOR Product IN (Apples, Bananas, Cantaloupe , Beer, [Magic mushrooms])) AS some_alias
ORDER BY Customer

SELECT	*
FROM	Pivoted_sales_table

SELECT	Customer, Product, Quantity
FROM	Pivoted_sales_table
	UNPIVOT(	Quantity FOR 
			Product IN (	Apples, Bananas, Cantaloupe 
, Beer, [Magic mushrooms])
) AS some_alias


--Determine the impact of NULL values in PIVOT and UNPIVOT queries
--Count(*) not allowed
SELECT	Product, Bill, John, Diana
FROM	Sales
	PIVOT (COUNT(Quantity) 
		FOR Customer IN (Bill, John, Diana)) AS some_alias
ORDER BY Product

SELECT	Customer, Apples, Bananas, Cantaloupe , Beer, [Magic mushrooms]
FROM	Sales
	PIVOT (MIN(Quantity), MAX(Quantity)
FOR Product IN (Apples, Bananas, Cantaloupe , Beer, [Magic mushrooms])) AS some_alias
ORDER BY Customer


USE TestDB
GO
DROP TABLE IF EXISTS Sales;
DROP TABLE IF EXISTS Pivoted_sales_table;

--Query temporal data and non-relational data

--Query historic data by using temporal tables
USE WideWorldImporters
GO

SELECT	CountryName, LatestRecordedPopulation
FROM	Application.Countries

SELECT	CountryName, LatestRecordedPopulation
FROM	Application.Countries
FOR SYSTEM_TIME AS OF '2013-01-01 00:00:00.0000000'
WHERE	CountryName = 'Australia'

SELECT	CountryName, LatestRecordedPopulation, ValidFrom, ValidTo
FROM	Application.Countries
FOR SYSTEM_TIME ALL
WHERE	CountryName = 'Australia'

SELECT CountryName, LatestRecordedPopulation, ValidFrom, ValidTo
FROM	Application.Countries
FOR	SYSTEM_TIME 	FROM '2013-07-01 16:00:00.0000000' 
TO '2015-07-01 16:00:00.0000000'
WHERE	CountryName = 'Australia'

SELECT	CountryName, LatestRecordedPopulation, ValidFrom, ValidTo
FROM	Application.Countries
FOR	SYSTEM_TIME 	BETWEEN '2013-07-01 16:00:00.0000000' 
AND '2015-07-01 16:00:00.0000000'
WHERE	CountryName = 'Australia'

DECLARE @now datetime2 = SYSDATETIME()
SELECT	CountryName, LatestRecordedPopulation, ValidFrom, ValidTo
FROM	Application.Countries
FOR	SYSTEM_TIME CONTAINED IN ('2013-07-01 15:00:00.0000000', @now)
WHERE	CountryName = 'Australia'

SELECT	CountryName, LatestRecordedPopulation, ValidFrom, ValidTo
FROM	Application.Countries_archive
WHERE	CountryName = 'Australia'
UNION ALL
SELECT	CountryName, LatestRecordedPopulation, ValidFrom, ValidTo
FROM	Application.Countries
WHERE	CountryName = 'Australia'

USE TestDB
GO
IF EXISTS (	SELECT * 
FROM 	sys.tables 
WHERE 	name = 'Countries' 
AND temporal_type_desc = 'SYSTEM_VERSIONED_TEMPORAL_TABLE')
BEGIN
	ALTER TABLE Countries SET ( SYSTEM_VERSIONING = OFF)
END
GO

DROP TABLE IF EXISTS Countries_archive
DROP TABLE IF EXISTS Countries
GO

CREATE TABLE Countries (
	CountryID		int IDENTITY PRIMARY KEY
	,CountryName	varchar(50)
	,Population		int
	,ValidFrom		datetime2 GENERATED ALWAYS AS ROW START HIDDEN
	,ValidTo		datetime2 GENERATED ALWAYS AS ROW END HIDDEN
	,PERIOD FOR SYSTEM_TIME (ValidFrom,ValidTo)) 
		WITH(SYSTEM_VERSIONING = ON (HISTORY_TABLE = dbo.Countries_archive))
GO

INSERT Countries (CountryName, Population) VALUES ('Neverland', 100)
UPDATE Countries SET Population = 101 WHERE CountryName = 'Neverland'

SELECT	*, ValidFrom, ValidTo
FROM	Countries
	FOR SYSTEM_TIME ALL
ORDER BY ValidFrom

BEGIN TRAN
	UPDATE Countries SET Population = 102 WHERE CountryName = 'Neverland'
	WAITFOR DELAY '00:00:10'
	UPDATE Countries SET Population = 103 WHERE CountryName = 'Neverland'
COMMIT TRAN

SELECT	*, ValidFrom, ValidTo
FROM	Countries
	FOR SYSTEM_TIME ALL
ORDER BY ValidFrom

SELECT	*
FROM	countries_archive

DECLARE @local_time datetime2
	,@utc_time datetime2
SET @local_time = '2018-07-04 13:40:00'

SET @utc_time = DATEADD(second, DATEDIFF(second, SYSDATETIME(), SYSUTCDATETIME()), @local_time)

SELECT	*	
FROM	Countries
	FOR SYSTEM_TIME AS OF @utc_time

DELETE FROM Countries_archive WHERE ValidTo <DATEADD(yy, -7, SYSUTCDATETIME())

ALTER TABLE Countries ADD Description varchar(100) NULL 
GO
UPDATE Countries SET Description = 'Not an actual country' WHERE CountryName = 'Neverland'

GO
ALTER TABLE Countries DROP COLUMN Description

USE TestDB
GO
IF EXISTS (	SELECT * 
FROM 	sys.tables 
WHERE 	name = 'Countries' 
AND temporal_type_desc = 'SYSTEM_VERSIONED_TEMPORAL_TABLE')
BEGIN
	ALTER TABLE Countries SET ( SYSTEM_VERSIONING = OFF)
END
GO

DROP TABLE IF EXISTS Countries_archive
DROP TABLE IF EXISTS Countries
GO

CREATE TABLE Countries (
	CountryID	int IDENTITY PRIMARY KEY NOT NULL
	,CountryName	varchar(50)
	,Population	int)
GO

INSERT Countries (CountryName, Population) VALUES ('Neverland', 103)

CREATE TABLE Countries_archive (
	CountryID	int NOT NULL --no identity or primary key
	,CountryName	varchar(50)
	,Population	int)
GO

ALTER TABLE Countries_archive ADD ValidFrom datetime2 NOT NULL
ALTER TABLE Countries_archive ADD ValidTo datetime2 NOT NULL
GO
INSERT Countries_archive (CountryID, CountryName, Population, ValidFrom,ValidTo) 
VALUES (1, 'Neverland', 100, '2011-01-01', '2012-01-01') 

ALTER TABLE Countries ADD ValidFrom datetime2  NULL
ALTER TABLE Countries ADD ValidTo datetime2  NULL
GO
UPDATE Countries SET ValidFrom = '2012-01-01' 
UPDATE Countries SET ValidTo = '9999-12-31 23:59:59.9999999'
GO

ALTER TABLE Countries ALTER COLUMN ValidFrom datetime2 NOT NULL
ALTER TABLE Countries ALTER COLUMN ValidTo datetime2 NOT NULL
GO

ALTER TABLE Countries ADD PERIOD FOR SYSTEM_TIME (ValidFrom,ValidTo)
ALTER TABLE Countries SET (SYSTEM_VERSIONING = ON (HISTORY_TABLE = dbo.Countries_archive))

SELECT  [2012].population - [2011].population AS 'population growth'
FROM	Countries FOR SYSTEM_TIME AS OF '2011-01-01' AS [2011]
	INNER JOIN Countries FOR SYSTEM_TIME AS OF '2012-01-01' AS [2012] 
	ON [2011].CountryID = [2012].CountryID

--Query and output JSON data
CREATE TABLE [dbo].[Employees](
	[EmployeeID] [tinyint] IDENTITY(1,1) NOT NULL,
	[FirstName] [varchar](100) NULL,
	[LastName] [varchar](50) NULL,
	[Address] [varchar](100) NULL,
	[Employee_Number] [int] NULL
) 

INSERT dbo.Employees (FirstName, LastName, Address) 
VALUES ('Bob', 'Jackson', 'Under the bridge')
	,('Bo', 'Didley', 'Home of mr. Bo Didley')

DECLARE @json NVARCHAR(MAX)
SET @json = '{"FirstName":"Bob"}'

SELECT ISJSON(@json) AS 'IsValidJSON?'

SELECT	FirstName, lastname, address
FROM	employees
WHERE	EmployeeID = 1
FOR JSON AUTO

--Format query output as JSON
SELECT	FirstName, lastname, address
FROM	employees
WHERE	EmployeeID in (1,2)
FOR JSON AUTO

SELECT	FirstName, lastname, address
FROM	employees
WHERE	EmployeeID in (1,2)
FOR JSON PATH

SELECT	FirstName, lastname, address
FROM	employees
WHERE	EmployeeID in (1,2)
FOR JSON PATH, ROOT ('Employees')

SELECT	FirstName, lastname, address
FROM	employees
WHERE	EmployeeID in (1,2)
FOR JSON PATH, WITHOUT_ARRAY_WRAPPER

UPDATE	Employees 
SET	Employee_Number = employeeID 
WHERE	EmployeeID = 1

SELECT	FirstName, lastname, address, Employee_Number
FROM	employees
WHERE	EmployeeID in (1,2)
FOR JSON PATH,  INCLUDE_NULL_VALUES

SELECT	FirstName AS 'Name.FirstName'
	, lastname AS 'Name.LastName'
	, address
FROM	employees
WHERE	EmployeeID in (1,2)
FOR JSON PATH

--Extract data from JSON
DECLARE @json NVARCHAR(MAX)

SET @json = '{
	"A null value":null
	,"A text string":"string"
	,"A number":2
	,"A boolean (true or false)":true
	,"A boolean (true or false)":false
	,"An array":[1,2,3]
	,"An object": {"key1":"value1", "key2":"value2"}
}'

SELECT	*
FROM	OPENJSON(@json)

SELECT	[key], value
FROM	OPENJSON(@json)
WHERE	type <> 0

SELECT	[key], value
FROM	OPENJSON(@json,'$."An object"')

SELECT	[key], value
FROM	OPENJSON(@json,'$."An array"')

SELECT	[key], value
FROM	OPENJSON(@json,'lax $."n array"')

SELECT	[key], value
FROM	OPENJSON(@json,'strict $."n array"')

SELECT	*
FROM	OPENJSON(@json)
	WITH (
		NameOfTheColumn		bigint		'$."A number"'
		,NameOfTheOtherColumn	varchar(100)	'$."A text string"'
		)

SELECT	*
FROM	OPENJSON(@json)
	WITH (
		NameOfTheColumn		bigint		'$."A number"'
		,NameOfTheOtherColumn	varchar(100)	'$."A text string"'
		,JSONColumn  			nvarchar(max) '$."An object"' AS JSON
		,ObjectValue 			varchar(100) 	'$."An object".key1'
		)

SELECT JSON_VALUE(@json, '$."A number"')

SELECT JSON_QUERY(@json, '$."An object"')

SELECT JSON_QUERY(@json, '$."A number"')
SELECT JSON_VALUE(@json, '$."An object"')

SELECT JSON_MODIFY(@json,'$."A number"', 17)

SELECT JSON_VALUE(@json, '$.Employees[1].address')

--Query and output XML data
DECLARE @xml XML
SET @XML = '<FirstName>Bob</Firstname>'

SELECT @xml

SELECT TRY_CAST('<FirstName>Bob</Firstname>' as XML)

SELECT	EmployeeID as '@Id'
	,FirstName
	,LastName
FROM	Employees
WHERE	EmployeeID in (1,2)
FOR XML PATH ('Employee')

--Format query output as XML
SELECT	EmployeeID 
	,FirstName 
	,LastName
FROM	Employees
WHERE	EmployeeID in (1,2)
FOR XML RAW

SELECT	EmployeeID 
	,FirstName 
	,LastName
FROM	Employees
WHERE	EmployeeID in (1,2)
FOR XML RAW ('GiveThisElementAnotherName')

SELECT	EmployeeID 
	,FirstName 
	,LastName
FROM	Employees
WHERE	EmployeeID in (1,2)
FOR XML RAW , ELEMENTS

SELECT	EmployeeID 
	,FirstName 
	,LastName
	,Employee_Number
FROM	Employees
WHERE	EmployeeID in (1,2)
FOR XML RAW

SELECT	EmployeeID 
	,FirstName 
	,LastName
	,Employee_Number
FROM	Employees
WHERE	EmployeeID in (1,2)
FOR XML RAW, ELEMENTS XSINIL

SELECT	EmployeeID 
	,FirstName 
	,LastName
FROM	Employees
WHERE	EmployeeID in (1,2)
FOR XML RAW, ROOT ('Employees')

SELECT	c.Customername, o.orderid,  OrderDate
FROM	sales.Orders o
	INNER JOIN sales.Customers c on c.CustomerID = o.CustomerID
WHERE	c.customerId in (832, 803)
	AND YEAR(OrderDate)=2013 
	AND MONTH(OrderDate)=1 
--ORDER BY OrderDate
FOR XML AUTO

SELECT	EmployeeID as '@Id'
	,FirstName
	,LastName
FROM	Employees
WHERE	EmployeeID in (1,2)
FOR XML PATH ('Employee')

--outer query
SELECT	c.CustomerID AS '@id'
	,c.Customername
	--subquery will be inserted here
FROM	sales.customers c	
WHERE	c.customerId in (832, 803)
ORDER BY c.CustomerName
FOR XML PATH ('Customers'), ELEMENTS, ROOT ('CustomerOrders')

--subquery
SELECT	o.orderid AS '@OrderID'
	,o.OrderDate 
FROM	sales.customers c2
	INNER JOIN sales.orders o on c2.CustomerID = o.CustomerID
WHERE	c.customerID = c2.customerID
	AND YEAR(OrderDate)=2013 
	AND MONTH(OrderDate)=1 		
FOR XML PATH('Orders'), ROOT('CustomerOrderId'),TYPE

--full query
SELECT	c.CustomerID AS '@id'
		,c.Customername
		,(SELECT	o.orderid AS '@OrderID'
				,o.OrderDate 
			FROM	sales.customers c2
				INNER JOIN sales.orders o on c2.CustomerID = o.CustomerID
			WHERE	c.customerID = c2.customerID
				AND YEAR(OrderDate)=2013 
				AND MONTH(OrderDate)=1 		
			FOR XML PATH('Orders'), ROOT('CustomerOrderId'),TYPE)
FROM	sales.customers c	
WHERE	c.customerId in (832, 803)
ORDER BY c.CustomerName
FOR XML PATH ('Customers'), ELEMENTS, ROOT ('CustomerOrders')

SELECT	ol.orderlineId as '@OrderLineID'
	,ol.Description
	,ol.Quantity
FROM	sales.orderlines ol
	inner join sales.orders o2 on ol.OrderID = o2.OrderID
	inner join sales.customers c3 on c3.CustomerID = o.CustomerID
WHERE	 o2.OrderID = o.orderid
FOR XML PATH ('OrderLines'), TYPE


DECLARE @xml varchar(1000)
DECLARE @xml_document_handle int

SET @xml = '
<CustomerOrders>
  <Customers id="832">
    <Customername>Aakriti Byrraju</Customername>
  </Customers>
  <Customers id="803">
    <Customername>Bala Dixit</Customername>
  </Customers>
</CustomerOrders>
'

-- Step 1
EXEC  sp_xml_preparedocument @xml_document_handle OUTPUT, @xml;  

--Step 2
SELECT    *  
FROM      OPENXML (@xml_document_handle, '/CustomerOrders/Customers',11)  
          WITH (	id		int,  
			Customername	varchar(200)); 

--Step 3
EXEC	sp_xml_removedocument @xml_document_handle

--XML output of customers, orders and order lines
SELECT	c.CustomerID AS '@id'
	,c.Customername
	, (SELECT	o.orderid AS '@OrderID'
			,o.OrderDate 
			,(SELECT ol.orderlineId as '@OrderLineID'
				,ol.Description
				,ol.Quantity
			FROM	sales.orderlines ol
				inner join sales.orders o2 on ol.OrderID = o2.OrderID
				inner join sales.customers c3 
on c3.CustomerID = o.CustomerID
			WHERE	 o2.OrderID = o.orderid
			for XML PATH ('OrderLines'), TYPE
			)
	FROM	sales.customers c2
		INNER JOIN sales.orders o on c2.CustomerID = o.CustomerID
	WHERE	c.customerID = c2.customerID
		AND YEAR(OrderDate)=2013 
		AND MONTH(OrderDate)=1 		
	FOR XML PATH('Orders'), ROOT('CustomerOrderId'),TYPE)
FROM	sales.customers c	
WHERE	c.customerId in (832, 803)
ORDER BY c.CustomerName
FOR XML PATH ('Customers'), ELEMENTS, ROOT ('CustomerOrders')

DECLARE @xml varchar(max)
DECLARE @xml_document_handle int

SET @xml = '
<CustomerOrders>
  <Customers id="832">
    <Customername>Aakriti Byrraju</Customername>
    <CustomerOrderId>
      <Orders OrderID="1">
        <OrderDate>2013-01-02</OrderDate>
        <OrderLines OrderLineID="2">
          <Description>Ride on toy sedan car (Black) 1/12 scale</Description>
          <Quantity>10</Quantity>
        </OrderLines>
      </Orders>
      <Orders OrderID="45">
        <OrderDate>2013-01-01</OrderDate>
        <OrderLines OrderLineID="1">
          <Description>32 mm Double sided bubble wrap 50m</Description>
          <Quantity>50</Quantity>
        </OrderLines>
      </Orders>
    </CustomerOrderId>
  </Customers>
  <Customers id="803">
    <Customername>Bala Dixit</Customername>
    <CustomerOrderId>
      <Orders OrderID="2">
        <OrderDate>2013-01-01</OrderDate>
        <OrderLines OrderLineID="3">
          <Description>Developer joke mug - old C developers never die (White)</Description>
          <Quantity>9</Quantity>
        </OrderLines>
        <OrderLines OrderLineID="6">
          <Description>USB food flash drive - chocolate bar</Description>
          <Quantity>9</Quantity>
        </OrderLines>
      </Orders>
    </CustomerOrderId>
  </Customers>
</CustomerOrders>
'

-- Step 1
EXEC  sp_xml_preparedocument @xml_document_handle OUTPUT, @xml;  

--Step 2
SELECT    *  
FROM      OPENXML (@xml_document_handle, '/CustomerOrders/Customers/CustomerOrderId/Orders/OrderLines',11)  
          WITH (	id	int '../../../@id',  
			Customername	varchar(1000) '../../../Customername',
			OrderDate	date '../OrderDate',
			OrderID	int '../@OrderID', 
			Description	varchar(1000)); 

--Step 3
EXEC	sp_xml_removedocument @xml_document_handle


--XQuery
SELECT @xml.query('/CustomerOrders/Customers/CustomerOrderId/Orders/OrderLines')

SELECT @xml.query('(/CustomerOrders/Customers/CustomerOrderId/Orders/OrderLines)[2]')

SELECT @xml.query('(/CustomerOrders/Customers[2]/CustomerOrderId/Orders/OrderLines)[2]')

SELECT @xml.query('(/CustomerOrders/Customers[@id=803]/CustomerOrderId/Orders/OrderLines)')

SELECT @xml.query('(/CustomerOrders/Customers[Customername="Bala Dixit"]/CustomerOrderId/Orders/OrderLines)')

--FLWOR
SELECT @xml.query('
		for $Orders in /CustomerOrders/Customers/CustomerOrderId/Orders
		return ($Orders)
		')

SELECT @xml.query('
for $Orders in /CustomerOrders/Customers/CustomerOrderId/Orders
return string($Orders)
')

SELECT @xml.query('
	for $Orders in /CustomerOrders/Customers/CustomerOrderId/Orders
	let $Quantity :=$Orders/OrderLines/Quantity
	where $Quantity > 20
	return ($Orders)
	')

SELECT @xml.query('
		for $Orders in /CustomerOrders/Customers/CustomerOrderId/Orders
		order by $Orders/@OrderID
		return $Orders
		')

--XQuery value
SELECT @xml.value('(/CustomerOrders/Customers[2]/CustomerOrderId/Orders/OrderLines)[1]', 'varchar(1000)')

SELECT @xml.value('(/CustomerOrders/Customers[2]/CustomerOrderId/Orders/OrderLines)[1]', 'int')

--XQuery exist
SELECT @xml.exist('(/CustomerOrders/Customers/CustomerOrderId/Orders/OrderLines)[5]')

SELECT @xml.exist('(/CustomerOrders/Customers[@id] = 832)')

--XQuery nodes
SELECT XML_table.value('../../../@id', N'int') as customerid
	,XML_table.value('../../../Customername[1]', 'varchar(100)') as customername
	,XML_table.value('../@OrderID', 'varchar(100)') as Orderid
	,XML_table.value('@OrderLineID', 'varchar(100)') as OrderLineid
	,XML_table.value('Quantity[1]', 'varchar(100)') as quantity
	,XML_table.value('Description[1]', 'varchar(100)') as description
FROM    @xml.nodes('/CustomerOrders/Customers/CustomerOrderId/Orders/OrderLines') as t(XML_table)
ORDER BY customerid desc

SELECT XML_table.value('../../@id', N'int') as customerid
	,XML_table.value('@OrderID', N'int') as orderID
	,XML_table.query('.') as orderdetails
FROM   @xml.nodes('/CustomerOrders/Customers/CustomerOrderId/Orders') as t(XML_table)

--XQuery modify
DECLARE @xml XML

SET @xml = '
<Employees>
	<Employee Id="1">
	  <FirstName>Bob</FirstName>
	  <LastName>Jackson</LastName>
	</Employee>
	<Employee Id="2">
	  <FirstName>Bo</FirstName>
	  <LastName>Didley</LastName>
	</Employee>
</Employees>
'
SET @xml.modify('
insert attribute SSID {"idontknow"}
into (/Employees/Employee)[2]
')

SET @xml.modify('
insert <Employee Id="3"><FirstName>Jeff</FirstName><LastName>Williams</LastName></Employee>
after (/Employees/Employee)[2]
')

SET @xml.modify('
insert <Employee Id="3"><FirstName>Jeff</FirstName><LastName>Williams</LastName></Employee>
into (/Employees)[1]
')


--XQuery delete
SET @xml.modify('
delete /Employees/Employee[2]/@SSID
')

SET @xml.modify('
delete /Employees/Employee[2]/Address
')
If the element or attribute isn’t present, no error will be returned.

SET @xml.modify('
replace value of (/Employees/Employee[2]/@SSID)[1]
with "001-002-003"
')

SET @xml.modify('
replace value of (/Employees/Employee[2]/Address/text())[1]
with "Beverly Hills"
')

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USE WideWorldImporters;

/* Query data by using subqueries and APPLY */

-- 001

-- simple subquery

SELECT o.*

FROM (SELECT * FROM Sales.Orders) o

-- 002

SELECT *

FROM [Application].[People]

WHERE PreferredName IN ( SELECT CustomerName

FROM sales.Customers )

-- 003

USE TestDB;

SELECT *

,(SELECT AVG(salary) FROM dbo.Employees) AS average_salary

FROM dbo.Employees

-- 004

SELECT *

FROM dbo.Employees

WHERE Salary > (SELECT AVG(salary) FROM dbo.Employees)

-- 005

-- correlated subquery

SELECT *

FROM dbo.Employees e1

WHERE Salary > ( SELECT AVG(salary)

FROM Employees e2

WHERE e1.department = e2.department)

-- 006

SELECT *

FROM dbo.Employees e1

INNER JOIN (SELECT AVG(salary) AS avg_salary, department

FROM dbo.employees

GROUP BY department) e2 ON e1.Department = e2.Department

WHERE salary > e2.avg_salary

-- 007

SELECT *

, (SELECT AVG(salary) FROM Employees e2 WHERE e1.department = e2.Department)

FROM Employees e1

WHERE Salary > ( SELECT AVG(salary)

FROM Employees e2

WHERE e1.Department = e2.department)

-- 008

SELECT *

FROM Departments d

WHERE ( SELECT count (*)

FROM Employees e

WHERE e.Department = d.Department) > 2

-- 009

ALTER TABLE Departments ADD Location varchar(100) DEFAULT 'Houston' WITH VALUES;

UPDATE Departments

SET Location = 'New York'

WHERE Department = 'Management'

/* Evaluate performance differences between table joins and correlated subqueries based on provided data and query plans */

-- 010

SELECT *

INTO Customers_copy

FROM WideWorldImporters.sales.Customers

SELECT *

INTO orders_copy

FROM WideWorldImporters.sales.orders

-- 011

-- join faster

SELECT c.CustomerName, o.lastorderdate, o.NumberOfOrders

FROM (SELECT customerID, max(orderdate) AS LastOrderDate, count(*) AS NumberOfOrders

FROM orders_copy

GROUP BY CustomerID) o

INNER JOIN Customers_copy c on c.CustomerID = o.customerId

SELECT CustomerName

,( SELECT MAX(orderdate)

FROM orders_copy o

WHERE c.customerId = o.customerID ) AS LastOrderDate

,( SELECT COUNT(*)

FROM orders_copy o

WHERE c.customerId = o.customerID )AS NumberOfOrders

FROM Customers_copy c

-- 012

-- correlated subquery faster

SELECT *

FROM Customers_copy c

LEFT OUTER JOIN orders_copy o on c.CustomerID = o.CustomerID

WHERE o.CustomerID IS NULL

SELECT *

FROM Customers_copy c

WHERE NOT EXISTS ( SELECT *

FROM orders_copy o

WHERE c.CustomerID = o.CustomerID)

/* Distinguish between the use of CROSS APPLY and OUTER APPLY */

-- 013

SELECT *

FROM Departments d

CROSS APPLY

( SELECT *

FROM Employees e

WHERE e.Department = d.Department) table_alias

SELECT *

FROM Departments d

INNER JOIN Employees e ON d.Department = e.Department

-- 014

INSERT Departments VALUES ('Research', 'Eindhoven')

SELECT *

FROM Departments d

OUTER APPLY

( SELECT *

FROM Employees e

WHERE e.Department = d.Department) table_alias

SELECT *

FROM Departments d

LEFT OUTER JOIN Employees e ON d.Department = e.Department

-- 015

CREATE FUNCTION dbo.fn_GetListOfEmployees(@Department AS varchar(100))

RETURNS TABLE

RETURN

(

SELECT FirstName + ' ' + LastName AS FullName, Salary

FROM Employees e

WHERE e.Department = @Department

)

-- 016

SELECT *

FROM dbo.fn_GetListOfEmployees('Engineering')

-- 017

SELECT *

FROM Departments d

CROSS APPLY dbo.fn_GetListOfEmployees(d.Department)

-- 018

SELECT session_id, DB_NAME(database_id) AS [database], start_time

, open_transaction_count, [text] AS [Query]

FROM sys.dm_exec_requests r

CROSS APPLY sys.dm_exec_sql_text(r.plan_handle) s

WHERE session_id > 50 -- Exclude system spids

ORDER BY session_id;

/* Query data by using table expressions */

--Identify basic components of table expressions

SELECT o.*

FROM (SELECT * FROM Sales.Orders) o

-- common table expression

WITH o

AS ( SELECT *

FROM Sales.Orders)

SELECT *

FROM o

SELECT *

FROM dbo.Employees e1

WHERE Salary > ( SELECT AVG(salary)

FROM Employees e2

WHERE e1.Department = e2.department);

-- readability example

SELECT c.CustomerName, o.lastorderdate, o.NumberOfOrders

FROM (SELECT customerID, max(orderdate) AS LastOrderDate, count(*) AS NumberOfOrders

FROM orders_copy

GROUP BY CustomerID) o

INNER JOIN Customers_copy c on c.CustomerID = o.customerId;

WITH o AS (

SELECT customerID, max(orderdate) AS LastOrderDate, count(*) AS NumberOfOrders

FROM orders_copy

GROUP BY CustomerID)

SELECT c.CustomerName, o.lastorderdate, o.NumberOfOrders

FROM o

INNER JOIN Customers_copy c on c.CustomerID = o.customerId

--Construct recursive table expressions to meet business requirements

-- Recursive cte, top to bottom:

ALTER TABLE Employees ADD ManagerID tinyint NULL;

INSERT Employees (FirstName,LastName, Salary, Department, ManagerID)

VALUES ('Harriet', 'Hughes', 1800.00,'Sales',7);

INSERT Employees (FirstName,LastName, Salary, Department, ManagerID)

VALUES ('Ronnie', 'Robertson', 1800.00,'Engineering',7);

UPDATE Employees

SET ManagerID = (SELECT EmployeeID FROM Employees WHERE FirstName = 'Harriet')

WHERE Department = 'Sales' AND FirstName <> 'Harriet'

UPDATE Employees

SET ManagerID = (SELECT EmployeeID FROM Employees WHERE FirstName = 'Ronnie')

WHERE Department = 'Engineering' AND FirstName <> 'Ronnie'

ALTER TABLE Employees ADD CONSTRAINT PK_EmployeeID PRIMARY KEY (EmployeeID)

ALTER TABLE Employees ADD CONSTRAINT FK_EmployeeID FOREIGN KEY (ManagerID) REFERENCES Employees(EmployeeID)

WITH Employee_CTE AS (

SELECT EmployeeID, ManagerID, Firstname + ' ' + LastName AS Name, 0 as Level

FROM Employees

WHERE ManagerID IS NULL

UNION ALL

SELECT e1.EmployeeID, e1.ManagerID, Firstname + ' ' + LastName, e2.level + 1

FROM Employees e1

INNER JOIN Employee_CTE e2 ON e2.EmployeeID = e1.ManagerID

)

SELECT Name, Level

FROM Employee_CTE

ORDER BY Level, Name

-- Recursive cte, bottom to top:

WITH Employee_CTE AS (

SELECT EmployeeID, ManagerID, Firstname + ' ' + LastName AS Name, 0 as Level

FROM Employees

WHERE EmployeeID NOT IN (SELECT ManagerID FROM Employees WHERE ManagerID IS NOT NULL)

UNION ALL

SELECT e1.EmployeeID, e1.ManagerID, Firstname + ' ' + LastName, e2.level + 1

FROM Employees e1

INNER JOIN Employee_CTE e2 ON e1.EmployeeID = e2.ManagerID

)

SELECT DISTINCT Name, Level

FROM Employee_CTE

ORDER BY Level, Name

-- Recursive CTE, final example

WITH Employee_CTE AS (

SELECT EmployeeID, ManagerID, 0 as Level

FROM Employees

WHERE EmployeeID NOT IN (SELECT ManagerID FROM Employees WHERE ManagerID IS NOT NULL)

UNION ALL

SELECT e1.EmployeeID, e1.ManagerID, e2.level + 1

FROM Employees e1

INNER JOIN Employee_CTE e2 ON e1.EmployeeID = e2.ManagerID

)

Distinct_CTE AS (

SELECT DISTINCT EmployeeID, ManagerID, Level

FROM Employee_CTE)

SELECT e2.FirstName + ' ' + e2.LastName AS Name, e3.FirstName + ' ' + e3.LastName AS Manager, Level

FROM Distinct_CTE e1

INNER JOIN Employees e2 ON e1.employeeID = e2.EmployeeID

LEFT OUTER JOIN Employees e3 ON e1.ManagerID = e3.EmployeeID

ORDER BY Level, Name

--multiple CTEs

WITH Employee_CTE AS (

SELECT EmployeeID, ManagerID, 0 as Level

FROM Employees

WHERE EmployeeID NOT IN ( SELECT ManagerID

FROM Employees

WHERE ManagerID IS NOT NULL)

UNION ALL

SELECT e1.EmployeeID, e1.ManagerID, e2.level + 1

FROM Employees e1

INNER JOIN Employee_CTE e2 ON e1.EmployeeID = e2.ManagerID

)

Distinct_CTE AS (

SELECT DISTINCT EmployeeID, ManagerID, Level

FROM Employee_CTE)

SELECT e2.FirstName + ' ' + e2.LastName AS Name

, e3.FirstName + ' ' + e3.LastName AS Manager, Level

FROM Distinct_CTE e1

INNER JOIN Employees e2 ON e1.employeeID = e2.EmployeeID

LEFT OUTER JOIN Employees e3 ON e1.ManagerID = e3.EmployeeID

ORDER BY Level, Name

--Temporary table

SELECT *

INTO #tmp_Employees

FROM Employees

SELECT *

FROM #tmp_Employees

ALTER TABLE #tmp_Employees ADD Description varchar(100) NULL

DROP TABLE #tmp_Employees

SELECT *

FROM tempdb.sys.objects

WHERE name LIKE '#tmp_Employees%'

--Table variables

DECLARE @Employees TABLE (

[EmployeeID] [tinyint] NOT NULL,

[FirstName] [varchar](100) NULL,

[LastName] [varchar](50) NULL,

[Address] [varchar](100) NULL,

[Salary] [decimal](18, 2) NULL,

[Department] [varchar](100) NULL,

[Employee_Number] [int] NULL,

[ManagerID] [tinyint] NULL)

INSERT INTO @Employees

SELECT *

FROM Employees

--Group and pivot data by using queries

--Construct complex GROUP BY clauses using GROUPING SETS, and CUBE

DROP TABLE IF EXISTS UFO_Sightings;

CREATE TABLE UFO_Sightings (

CountryID tinyint

, Country varchar(50)

, State varchar(50)

, City varchar(50)

, UFO_Sightings int );

INSERT INTO UFO_Sightings VALUES (1, 'Germany', NULL, 'Berlin', 1)

INSERT INTO UFO_Sightings VALUES (1, 'Germany', NULL, 'Frankfurt', 2)

INSERT INTO UFO_Sightings VALUES (1, 'Germany', NULL, 'Frankfurt', 3)

INSERT INTO UFO_Sightings VALUES (2, 'United States', 'Texas', 'Houston', 1)

INSERT INTO UFO_Sightings VALUES (2, 'United States', 'Texas', 'Paris', 2)

INSERT INTO UFO_Sightings VALUES (2, 'United States', 'Nevada', NULL, 300)

INSERT INTO UFO_Sightings VALUES (3, 'France', NULL, 'Paris', 1);

SELECT *

FROM UFO_Sightings

SELECT Country, SUM(UFO_Sightings)

FROM UFO_Sightings

GROUP BY Country

SELECT SUM(UFO_Sightings)

FROM UFO_Sightings

SELECT SUM(UFO_Sightings)

FROM UFO_Sightings

GROUP BY ()

SELECT Country, City, SUM(UFO_Sightings)

FROM UFO_Sightings

GROUP BY Country, City

ORDER BY Country, City;

SELECT Country, SUM(UFO_Sightings)

FROM UFO_Sightings

WHERE City <> 'Paris'

GROUP BY Country

SELECT Country, SUM(UFO_Sightings)

FROM UFO_Sightings

WHERE ISNULL(City,'') <> 'Paris'

GROUP BY Country

SELECT CountryID, Country, SUM(UFO_Sightings)

FROM UFO_Sightings

GROUP BY Country

SELECT Country, SUM(UFO_Sightings) AS TotalNumberOfSightings

FROM UFO_Sightings

GROUP BY Country

HAVING SUM(UFO_Sightings) > 100;

WITH ufo AS (

SELECT Country, SUM(UFO_Sightings) AS TotalNumberOfSightings

FROM UFO_Sightings

GROUP BY Country)

SELECT *

FROM ufo

WHERE TotalNumberOfSightings > 100

INSERT INTO UFO_Sightings VALUES (4, 'Belgium', NULL, 'Brussels', NULL);

SELECT Country, COUNT(UFO_Sightings) AS Count_1, COUNT(*) AS Count_2

FROM UFO_Sightings

GROUP BY Country

SELECT Country, State, SUM(UFO_Sightings) AS TotalUFO_Sightings

FROM UFO_Sightings

GROUP BY Country, State

--complex GROUP BY logic

SELECT Country, City, SUM(UFO_Sightings) AS TotalUFO_Sightings

FROM UFO_Sightings

GROUP BY Country, City

ORDER BY Country, City

SELECT Country, City, SUM(UFO_Sightings) AS TotalUFO_Sightings

FROM UFO_Sightings

GROUP BY ROLLUP (Country, City);

SELECT Country, NULL AS City, SUM(UFO_Sightings) AS TotalUFO_Sightings

FROM UFO_Sightings

GROUP BY Country

UNION ALL

SELECT Country, City, SUM(UFO_Sightings) AS TotalUFO_Sightings

FROM UFO_Sightings

GROUP BY Country, City

UNION ALL

SELECT NULL, NULL, SUM(UFO_Sightings) AS TotalUFO_Sightings

FROM UFO_Sightings

GROUP BY ()

GROUP BY Country, City WITH ROLLUP;

SELECT Country, GROUPING(Country) AS Is_result_of_grouping_countries

, State, GROUPING(State) AS Is_result_of_grouping_cities

FROM UFO_Sightings

GROUP BY Country, State WITH ROLLUP

SELECT CASE

WHEN GROUPING(Country) = 1 THEN 'Grand Total'

WHEN GROUPING(State) = 1 THEN 'Total for ' + Country

ELSE ''

END AS Totals

, Country

, State

,SUM(UFO_Sightings) AS TotalUFO_Sightings

FROM UFO_Sightings

GROUP BY Country, State WITH ROLLUP

SELECT Country, State, GROUPING_ID(Country, State )

FROM UFO_Sightings

GROUP BY Country, State WITH ROLLUP

ALTER TABLE UFO_Sightings ADD Continent varchar(100) NULL

GO --required batch separator, otherwise query will fail on missing column

UPDATE UFO_Sightings

SET Continent = 'Europe'

WHERE Country IN ('Germany', 'France', 'Belgium')

UPDATE UFO_Sightings

SET Continent = 'North America'

WHERE Country IN ('United States')

SELECT Continent

, Country

, State

, GROUPING_ID(Continent, Country, State )

, GROUPING(Continent) * 4 + GROUPING(Country) * 2 + GROUPING(State)

FROM UFO_Sightings

GROUP BY Continent, Country, State WITH ROLLUP

SELECT Country, City, SUM(UFO_Sightings) AS TotalUFO_Sightings

FROM UFO_Sightings

GROUP BY CUBE (Country, City)

ORDER BY 1, 2;

-- CUBE dissected: A & NULL, NULL & B, A & B, NULL & NULL

SELECT Country, NULL AS City, SUM(UFO_Sightings) AS TotalUFO_Sightings

FROM UFO_Sightings

GROUP BY (Country)

UNION ALL

SELECT NULL, City, SUM(UFO_Sightings) AS TotalUFO_Sightings

FROM UFO_Sightings

GROUP BY ( City)

UNION ALL

SELECT Country, City, SUM(UFO_Sightings) AS TotalUFO_Sightings

FROM UFO_Sightings

GROUP BY Country, City

UNION ALL

SELECT NULL, NULL, SUM(UFO_Sightings) AS TotalUFO_Sightings

FROM UFO_Sightings

ORDER BY 1, 2

SELECT Continent

, Country

, City

, SUM(UFO_Sightings) AS TotalUFO_Sightings

, GROUPING_ID(Continent,Country, City)

FROM UFO_Sightings

GROUP BY CUBE (Continent, Country, City)

ORDER BY 5;

SELECT Country, City, SUM(UFO_Sightings) AS TotalUFO_Sightings

FROM UFO_Sightings

GROUP BY GROUPING SETS ( Country, City)

SELECT Country, NULL, SUM(UFO_Sightings) AS TotalUFO_Sightings

FROM UFO_Sightings

GROUP BY Country

UNION ALL

SELECT NULL, City, SUM(UFO_Sightings) AS TotalUFO_Sightings

FROM UFO_Sightings

GROUP BY City

SELECT Country, City, SUM(UFO_Sightings) AS TotalUFO_Sightings

FROM UFO_Sightings

GROUP BY GROUPING SETS ( Country, City, ())

--Use windowing functions to group and rank the results of a query

DROP TABLE IF EXISTS Runner_info

CREATE TABLE Runner_info (

Runner varchar(50)

,Nickname varchar(50)

,Race varchar(50)

,Race_date date

,Distance decimal(8,3)

,Finish_time time)

INSERT Runner_info VALUES ('Jack', 'The Flash', 'New York marathon', '2016-11-06', 42.195, '2:53:00')

INSERT Runner_info VALUES ('Jack', 'The Flash', 'New York marathon', '2017-11-05', 42.195, '2:55:00')

INSERT Runner_info VALUES ('Jack', 'The Flash', 'Berlin marathon', '2016-09-25', 42.195, '2:45:00')

INSERT Runner_info VALUES ('Juan Gonzalez', 'Speedy', 'New York marathon', '2016-11-06', 42.195, '3:22:00')

INSERT Runner_info VALUES ('Juan Gonzalez', 'Speedy', 'New York marathon', '2017-11-05', 42.195, '3:18:30')

INSERT Runner_info VALUES ('Rudy', 'Roadrunner', 'New York marathon', '2016-11-06', 42.195, '4:01:00')

INSERT Runner_info VALUES ('Rudy', 'Roadrunner', 'New York marathon', '2017-11-05', 42.195, '4:05:30')

INSERT Runner_info VALUES ('Rudy', 'Roadrunner', 'Berlin marathon', '2016-09-25', 42.195, '3:59:59')

INSERT Runner_info VALUES ('Rudy', 'Roadrunner', 'Berlin marathon', '2017-09-24', 42.195, '4:13:00')

INSERT Runner_info VALUES ('Rudy', 'Roadrunner', 'Rotterdam half marathon', '2017-04-07', 21.1, '1:52')

SELECT *

FROM Runner_info

SELECT *

,COUNT(*) OVER () AS Nr_of_races_total

FROM Runner_info

SELECT *

,COUNT(*) OVER () AS Nr_of_races_total

,COUNT(*) OVER (PARTITION BY Runner) AS Nr_of_races_per_runner

FROM Runner_info

SELECT *

,COUNT(*) OVER (PARTITION BY Runner) AS Nr_of_races_per_runner

FROM Runner_info

WHERE Distance = 42.195

SELECT Runner

,Race

,Race_date

,Finish_time

,MIN(Finish_time) OVER (PARTITION BY Runner, Race) AS Race_PR

,DATEDIFF(mi,MIN(Finish_time) OVER (PARTITION BY Runner, Race), Finish_time) AS Slower_than_PR

FROM Runner_info

OVER ( PARTITION BY column

ORDER BY column

ROWS BETWEEN … AND …)

SELECT Runner, Race, Race_date, distance

,SUM(distance) OVER (PARTITION BY Runner

ORDER BY Race_date

ROWS BETWEEN UNBOUNDED PRECEDING AND CURRENT ROW)

AS Cumulative_distance

FROM Runner_info

WHERE Runner = 'Rudy'

ORDER BY Runner, Race_date

SELECT Runner, Race, Race_date, distance

,AVG(distance) OVER (PARTITION BY Runner

ORDER BY Race_date

ROWS BETWEEN 2 PRECEDING AND 2 FOLLOWING)

AS Running_average

FROM Runner_info

WHERE Runner = 'Rudy'

ORDER BY Runner, Race_date

INSERT Runner_info VALUES ('Rudy', 'Roadrunner', 'Ran home', '2017-11-05', 10, '1:10')

SELECT Runner, Race, Race_date, distance

,SUM(distance) OVER (PARTITION BY Runner

ORDER BY Race_date

ROWS BETWEEN UNBOUNDED PRECEDING AND CURRENT ROW)

AS Cumulative_distance

FROM Runner_info

WHERE Runner = 'Rudy'

ORDER BY Runner, Race_date

SELECT Runner, Race, Race_date, distance

,SUM(distance) OVER (PARTITION BY Runner

ORDER BY Race_date

RANGE BETWEEN UNBOUNDED PRECEDING AND CURRENT ROW)

AS Cumulative_distance

FROM Runner_info

WHERE Runner = 'Rudy'

ORDER BY Runner, Race_date

--Ranking window functions

SELECT Runner, Race, Race_date, Finish_time

,ROW_NUMBER() OVER (ORDER BY Finish_time) AS rownumber

,RANK() OVER (ORDER BY Finish_time) AS rank

,DENSE_RANK() OVER (ORDER BY Finish_time) AS denserank

,NTILE(5) OVER (ORDER BY Finish_time) AS ntile

FROM Runner_info

WHERE Distance = 42.195

ORDER BY rownumber

INSERT Runner_info VALUES ('Fred', 'The Shadow', 'New York marathon', '2016-11-06', 42.195, '2:53:00')

--Analytic window functions

SELECT FirstName, LastName, Department, Salary

FROM dbo.Employees

SELECT FirstName, LastName, Department, Salary

,LAG(Salary) OVER (ORDER BY Salary) as lag

,LEAD(Salary) OVER (ORDER BY Salary) as lead

FROM Employees

SELECT FirstName, LastName, Department, Salary

,LAG(Salary) OVER (ORDER BY Salary) as lag

,LEAD(Salary) OVER (ORDER BY Salary) as lead

FROM Employees

ORDER BY LastName

SELECT FirstName, LastName, Department, Salary

,LAG(Salary, 2) OVER (ORDER BY Salary) as lag

,LEAD(Salary, 2) OVER (ORDER BY Salary) as lead

FROM Employees

SELECT FirstName, LastName, Department, Salary

,LAG(Salary, 2, 'not applicable') OVER (ORDER BY Salary) as lag

,LEAD(Salary, 2, 'not applicable') OVER (ORDER BY Salary) as lead

FROM Employees

SELECT FirstName, LastName, Department, Salary

,LAG(Salary) OVER (PARTITION BY Department ORDER BY Salary) as lag

,LEAD(Salary) OVER (PARTITION BY Department ORDER BY Salary) as lead

FROM Employees

ORDER BY Department

SELECT FirstName, LastName, Department, Salary

,FIRST_VALUE(FirstName + ' ' + LastName)

OVER ( PARTITION BY Department

ORDER BY Salary)

as Least_earning_employee

,LAST_VALUE(FirstName + ' ' + LastName)

OVER ( PARTITION BY Department

ORDER BY Salary

RANGE BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING)

as Most_earning_employee

FROM Employees

ORDER BY Department, Salary

SELECT FirstName, LastName, Department, Salary

,CUME_DIST() OVER (ORDER BY Salary) as cumulative_distance

,CUME_DIST() OVER (ORDER BY Salary) * COUNT(*) OVER () as equal_or_less

FROM Employees

ORDER BY Salary

INSERT dbo.Employees (FirstName, LastName, Salary, Department)

VALUES ('James', 'Peterson', 900, 'Engineering')

SELECT FirstName, LastName, Department, Salary

,PERCENTILE_CONT(0.5) WITHIN GROUP (ORDER BY Salary) OVER () as median_salary

,PERCENTILE_DISC(0.5) WITHIN GROUP (ORDER BY Salary) OVER () as median_salary

FROM Employees

ORDER BY Salary

SELECT FirstName, LastName, Department, Salary

,PERCENT_RANK() OVER (ORDER BY Salary) as fraction_lower_than_this

,CAST(PERCENT_RANK() OVER (ORDER BY Salary) * 100 AS dec(5,1))

as percentage_lower_than_this

FROM Employees

ORDER BY Salary

--Construct PIVOT and UNPIVOT statements to return desired results based on supplied data

SELECT CustomerName, si.StockItemName, sum(quantity) as quantity

FROM sales.Customers c

INNER JOIN sales.Orders o on c.CustomerID = o.CustomerID

INNER JOIN sales.OrderLines ol on o.OrderID = ol.OrderID

INNER JOIN Warehouse.StockItems si on ol.StockItemID = si.StockItemID

WHERE c.CustomerID IN ( SELECT TOP 5 CustomerID

FROM Sales.Orders

GROUP BY CustomerID

ORDER BY COUNT(*))

AND si.StockItemID IN ( SELECT TOP 5 StockItemID

FROM Sales.Orderlines

GROUP BY StockItemID

ORDER BY COUNT(*))

GROUP BY CustomerName, si.StockItemName

ORDER BY CustomerName, si.StockItemName

--PIVOT and UNPIVOT

WITH cte AS(

SELECT CustomerName, si.StockItemName, quantity

FROM sales.Customers c

INNER JOIN sales.Orders o on c.CustomerID = o.CustomerID

INNER JOIN sales.OrderLines ol on o.OrderID = ol.OrderID

INNER JOIN Warehouse.StockItems si on ol.StockItemID = si.StockItemID

WHERE si.StockItemID IN ( SELECT TOP 5 StockItemID

FROM Sales.Orderlines

GROUP BY StockItemID

ORDER BY COUNT(*))

)

SELECT *

FROM cte

PIVOT (SUM(quantity)

FOR CustomerName IN ([Anand Mudaliyar],[Jibek Juniskyzy]

,[Agrita Abele],[Kalyani Benjaree],[Jaroslav Fisar]))

AS SalesQuantity

USE TestDB

DROP TABLE IF EXISTS Sales;

CREATE TABLE Sales(

Customer varchar(50)

, Product varchar(50)

, Quantity int)

INSERT INTO Sales(Customer, Product, Quantity)

VALUES('John','Apples',4)

,('John','Bananas',7)

,('John','Cantaloupe',1)

,('John','Apples',5)

,('John','Beer',6)

,('Bill','Cantaloupe',3)

,('Bill','Beer',24)

,('Diana','Apples',6)

,('Diana','Bananas',5)

,('Diana','Cantaloupe',2)

SELECT *

FROM Sales

-- Pivot customers

SELECT Product, Bill, John, Diana

FROM Sales

PIVOT (SUM(Quantity)

FOR Customer IN (Bill, John, Diana)) AS some_alias

ORDER BY Product

-- Pivot product

SELECT Customer, Apples, Bananas, Cantaloupe , Beer, [Magic mushrooms]

FROM Sales

PIVOT (SUM(Quantity)

FOR Product IN (Apples, Bananas, Cantaloupe , Beer, [Magic mushrooms])) AS some_alias

ORDER BY Customer

-- adding a column

ALTER TABLE Sales ADD CustomerID int NULL

UPDATE Sales SET CustomerID = 1 WHERE Customer = 'Bill'

UPDATE Sales SET CustomerID = 2 WHERE Customer = 'John'

UPDATE Sales SET CustomerID = 3 WHERE Customer = 'Diana'

SELECT Product, Bill, John, Diana

FROM Sales

PIVOT (SUM(Quantity)

FOR Customer IN (Bill, John, Diana)) AS some_alias

ORDER BY Product

ALTER TABLE Sales DROP CustomerID

SELECT Customer, Apples, Bananas, Cantaloupe , Beer, [Magic mushrooms]

INTO Pivoted_sales_table

FROM Sales

PIVOT (SUM(Quantity)

FOR Product IN (Apples, Bananas, Cantaloupe , Beer, [Magic mushrooms])) AS some_alias

ORDER BY Customer

SELECT *

FROM Pivoted_sales_table

SELECT Customer, Product, Quantity

FROM Pivoted_sales_table

UNPIVOT( Quantity FOR

Product IN ( Apples, Bananas, Cantaloupe

, Beer, [Magic mushrooms])

) AS some_alias

--Determine the impact of NULL values in PIVOT and UNPIVOT queries

--Count(*) not allowed

SELECT Product, Bill, John, Diana

FROM Sales

PIVOT (COUNT(Quantity)

FOR Customer IN (Bill, John, Diana)) AS some_alias

ORDER BY Product

SELECT Customer, Apples, Bananas, Cantaloupe , Beer, [Magic mushrooms]

FROM Sales

PIVOT (MIN(Quantity), MAX(Quantity)

FOR Product IN (Apples, Bananas, Cantaloupe , Beer, [Magic mushrooms])) AS some_alias

ORDER BY Customer

USE TestDB

DROP TABLE IF EXISTS Sales;

DROP TABLE IF EXISTS Pivoted_sales_table;

--Query temporal data and non-relational data

--Query historic data by using temporal tables

USE WideWorldImporters

SELECT CountryName, LatestRecordedPopulation

FROM Application.Countries

SELECT CountryName, LatestRecordedPopulation

FROM Application.Countries

FOR SYSTEM_TIME AS OF '2013-01-01 00:00:00.0000000'

WHERE CountryName = 'Australia'

SELECT CountryName, LatestRecordedPopulation, ValidFrom, ValidTo

FROM Application.Countries

FOR SYSTEM_TIME ALL

WHERE CountryName = 'Australia'

SELECT CountryName, LatestRecordedPopulation, ValidFrom, ValidTo

FROM Application.Countries

FOR SYSTEM_TIME FROM '2013-07-01 16:00:00.0000000'

TO '2015-07-01 16:00:00.0000000'

WHERE CountryName = 'Australia'

SELECT CountryName, LatestRecordedPopulation, ValidFrom, ValidTo

FROM Application.Countries

FOR SYSTEM_TIME BETWEEN '2013-07-01 16:00:00.0000000'

AND '2015-07-01 16:00:00.0000000'

WHERE CountryName = 'Australia'

DECLARE @now datetime2 = SYSDATETIME()

SELECT CountryName, LatestRecordedPopulation, ValidFrom, ValidTo

FROM Application.Countries

FOR SYSTEM_TIME CONTAINED IN ('2013-07-01 15:00:00.0000000', @now)

WHERE CountryName = 'Australia'

SELECT CountryName, LatestRecordedPopulation, ValidFrom, ValidTo

FROM Application.Countries_archive

WHERE CountryName = 'Australia'

UNION ALL

SELECT CountryName, LatestRecordedPopulation, ValidFrom, ValidTo

FROM Application.Countries

WHERE CountryName = 'Australia'

USE TestDB

IF EXISTS ( SELECT *

FROM sys.tables

WHERE name = 'Countries'

AND temporal_type_desc = 'SYSTEM_VERSIONED_TEMPORAL_TABLE')

BEGIN

ALTER TABLE Countries SET ( SYSTEM_VERSIONING = OFF)

END

DROP TABLE IF EXISTS Countries_archive

DROP TABLE IF EXISTS Countries

CREATE TABLE Countries (

CountryID int IDENTITY PRIMARY KEY

,CountryName varchar(50)

,Population int

,ValidFrom datetime2 GENERATED ALWAYS AS ROW START HIDDEN

,ValidTo datetime2 GENERATED ALWAYS AS ROW END HIDDEN

,PERIOD FOR SYSTEM_TIME (ValidFrom,ValidTo))

WITH(SYSTEM_VERSIONING = ON (HISTORY_TABLE = dbo.Countries_archive))

INSERT Countries (CountryName, Population) VALUES ('Neverland', 100)

UPDATE Countries SET Population = 101 WHERE CountryName = 'Neverland'

SELECT *, ValidFrom, ValidTo

FROM Countries

FOR SYSTEM_TIME ALL

ORDER BY ValidFrom

BEGIN TRAN

UPDATE Countries SET Population = 102 WHERE CountryName = 'Neverland'

WAITFOR DELAY '00:00:10'

UPDATE Countries SET Population = 103 WHERE CountryName = 'Neverland'

COMMIT TRAN

SELECT *, ValidFrom, ValidTo

FROM Countries

FOR SYSTEM_TIME ALL

ORDER BY ValidFrom

SELECT *

FROM countries_archive

DECLARE @local_time datetime2

,@utc_time datetime2

SET @local_time = '2018-07-04 13:40:00'

SET @utc_time = DATEADD(second, DATEDIFF(second, SYSDATETIME(), SYSUTCDATETIME()), @local_time)

SELECT *

FROM Countries

FOR SYSTEM_TIME AS OF @utc_time

DELETE FROM Countries_archive WHERE ValidTo <DATEADD(yy, -7, SYSUTCDATETIME())

ALTER TABLE Countries ADD Description varchar(100) NULL

UPDATE Countries SET Description = 'Not an actual country' WHERE CountryName = 'Neverland'

ALTER TABLE Countries DROP COLUMN Description

USE TestDB

IF EXISTS ( SELECT *

FROM sys.tables

WHERE name = 'Countries'

AND temporal_type_desc = 'SYSTEM_VERSIONED_TEMPORAL_TABLE')

BEGIN

ALTER TABLE Countries SET ( SYSTEM_VERSIONING = OFF)

END

DROP TABLE IF EXISTS Countries_archive

DROP TABLE IF EXISTS Countries

CREATE TABLE Countries (

CountryID int IDENTITY PRIMARY KEY NOT NULL

,CountryName varchar(50)

,Population int)

INSERT Countries (CountryName, Population) VALUES ('Neverland', 103)

CREATE TABLE Countries_archive (

CountryID int NOT NULL --no identity or primary key

,CountryName varchar(50)

,Population int)

ALTER TABLE Countries_archive ADD ValidFrom datetime2 NOT NULL

ALTER TABLE Countries_archive ADD ValidTo datetime2 NOT NULL

INSERT Countries_archive (CountryID, CountryName, Population, ValidFrom,ValidTo)

VALUES (1, 'Neverland', 100, '2011-01-01', '2012-01-01')

ALTER TABLE Countries ADD ValidFrom datetime2 NULL

ALTER TABLE Countries ADD ValidTo datetime2 NULL

UPDATE Countries SET ValidFrom = '2012-01-01'

UPDATE Countries SET ValidTo = '9999-12-31 23:59:59.9999999'

ALTER TABLE Countries ALTER COLUMN ValidFrom datetime2 NOT NULL

ALTER TABLE Countries ALTER COLUMN ValidTo datetime2 NOT NULL

ALTER TABLE Countries ADD PERIOD FOR SYSTEM_TIME (ValidFrom,ValidTo)

ALTER TABLE Countries SET (SYSTEM_VERSIONING = ON (HISTORY_TABLE = dbo.Countries_archive))

SELECT [2012].population - [2011].population AS 'population growth'

FROM Countries FOR SYSTEM_TIME AS OF '2011-01-01' AS [2011]

INNER JOIN Countries FOR SYSTEM_TIME AS OF '2012-01-01' AS [2012]

ON [2011].CountryID = [2012].CountryID

--Query and output JSON data

CREATE TABLE [dbo].[Employees](

[EmployeeID] [tinyint] IDENTITY(1,1) NOT NULL,

[FirstName] [varchar](100) NULL,

[LastName] [varchar](50) NULL,

[Address] [varchar](100) NULL,

[Employee_Number] [int] NULL

)

INSERT dbo.Employees (FirstName, LastName, Address)

VALUES ('Bob', 'Jackson', 'Under the bridge')

,('Bo', 'Didley', 'Home of mr. Bo Didley')

DECLARE @json NVARCHAR(MAX)

SET @json = '{"FirstName":"Bob"}'

SELECT ISJSON(@json) AS 'IsValidJSON?'

SELECT FirstName, lastname, address

FROM employees

WHERE EmployeeID = 1

FOR JSON AUTO

--Format query output as JSON

SELECT FirstName, lastname, address

FROM employees

WHERE EmployeeID in (1,2)

FOR JSON AUTO

SELECT FirstName, lastname, address

FROM employees

WHERE EmployeeID in (1,2)

FOR JSON PATH

SELECT FirstName, lastname, address

FROM employees

WHERE EmployeeID in (1,2)

FOR JSON PATH, ROOT ('Employees')

SELECT FirstName, lastname, address

FROM employees

WHERE EmployeeID in (1,2)

FOR JSON PATH, WITHOUT_ARRAY_WRAPPER

UPDATE Employees

SET Employee_Number = employeeID

WHERE EmployeeID = 1

SELECT FirstName, lastname, address, Employee_Number

FROM employees

WHERE EmployeeID in (1,2)

FOR JSON PATH, INCLUDE_NULL_VALUES

SELECT FirstName AS 'Name.FirstName'

, lastname AS 'Name.LastName'

, address

FROM employees

WHERE EmployeeID in (1,2)

FOR JSON PATH

--Extract data from JSON

DECLARE @json NVARCHAR(MAX)

SET @json = '{

"A null value":null

,"A text string":"string"

,"A number":2

,"A boolean (true or false)":true

,"A boolean (true or false)":false

,"An array":[1,2,3]

,"An object": {"key1":"value1", "key2":"value2"}

SELECT *

FROM OPENJSON(@json)

SELECT [key], value

FROM OPENJSON(@json)

WHERE type <> 0

SELECT [key], value

FROM OPENJSON(@json,'$."An object"')

SELECT [key], value

FROM OPENJSON(@json,'$."An array"')

SELECT [key], value

FROM OPENJSON(@json,'lax $."n array"')

SELECT [key], value

FROM OPENJSON(@json,'strict $."n array"')

SELECT *

FROM OPENJSON(@json)

WITH (

NameOfTheColumn bigint '$."A number"'

,NameOfTheOtherColumn varchar(100) '$."A text string"'

)

SELECT *

FROM OPENJSON(@json)

WITH (

NameOfTheColumn bigint '$."A number"'

,NameOfTheOtherColumn varchar(100) '$."A text string"'

,JSONColumn nvarchar(max) '$."An object"' AS JSON

,ObjectValue varchar(100) '$."An object".key1'

)

SELECT JSON_VALUE(@json, '$."A number"')

SELECT JSON_QUERY(@json, '$."An object"')

SELECT JSON_QUERY(@json, '$."A number"')

SELECT JSON_VALUE(@json, '$."An object"')

SELECT JSON_MODIFY(@json,'$."A number"', 17)

SELECT JSON_VALUE(@json, '$.Employees[1].address')

--Query and output XML data

DECLARE @xml XML

SET @XML = '<FirstName>Bob</Firstname>'

SELECT @xml

SELECT TRY_CAST('<FirstName>Bob</Firstname>' as XML)

SELECT EmployeeID as '@Id'

,FirstName

,LastName

FROM Employees

WHERE EmployeeID in (1,2)

FOR XML PATH ('Employee')

--Format query output as XML

SELECT EmployeeID

,FirstName

,LastName

FROM Employees

WHERE EmployeeID in (1,2)

FOR XML RAW

SELECT EmployeeID

,FirstName

,LastName

FROM Employees

WHERE EmployeeID in (1,2)

FOR XML RAW ('GiveThisElementAnotherName')

SELECT EmployeeID

,FirstName

,LastName

FROM Employees

WHERE EmployeeID in (1,2)

FOR XML RAW , ELEMENTS

SELECT EmployeeID

,FirstName

,LastName

,Employee_Number

FROM Employees

WHERE EmployeeID in (1,2)

FOR XML RAW

SELECT EmployeeID

,FirstName

,LastName

,Employee_Number

FROM Employees

WHERE EmployeeID in (1,2)

FOR XML RAW, ELEMENTS XSINIL

SELECT EmployeeID

,FirstName

,LastName

FROM Employees

WHERE EmployeeID in (1,2)

FOR XML RAW, ROOT ('Employees')

SELECT c.Customername, o.orderid, OrderDate

FROM sales.Orders o

INNER JOIN sales.Customers c on c.CustomerID = o.CustomerID

WHERE c.customerId in (832, 803)

AND YEAR(OrderDate)=2013

AND MONTH(OrderDate)=1

--ORDER BY OrderDate

FOR XML AUTO

SELECT EmployeeID as '@Id'

,FirstName

,LastName

FROM Employees

WHERE EmployeeID in (1,2)

FOR XML PATH ('Employee')

--outer query

SELECT c.CustomerID AS '@id'

,c.Customername

--subquery will be inserted here

FROM sales.customers c

WHERE c.customerId in (832, 803)

ORDER BY c.CustomerName

FOR XML PATH ('Customers'), ELEMENTS, ROOT ('CustomerOrders')

--subquery

SELECT o.orderid AS '@OrderID'

,o.OrderDate

FROM sales.customers c2

INNER JOIN sales.orders o on c2.CustomerID = o.CustomerID

WHERE c.customerID = c2.customerID

AND YEAR(OrderDate)=2013

AND MONTH(OrderDate)=1

FOR XML PATH('Orders'), ROOT('CustomerOrderId'),TYPE

--full query

SELECT c.CustomerID AS '@id'

,c.Customername

,(SELECT o.orderid AS '@OrderID'

,o.OrderDate

FROM sales.customers c2

INNER JOIN sales.orders o on c2.CustomerID = o.CustomerID

WHERE c.customerID = c2.customerID

AND YEAR(OrderDate)=2013

AND MONTH(OrderDate)=1

FOR XML PATH('Orders'), ROOT('CustomerOrderId'),TYPE)

FROM sales.customers c

WHERE c.customerId in (832, 803)

ORDER BY c.CustomerName

FOR XML PATH ('Customers'), ELEMENTS, ROOT ('CustomerOrders')

SELECT ol.orderlineId as '@OrderLineID'

,ol.Description

,ol.Quantity

FROM sales.orderlines ol

inner join sales.orders o2 on ol.OrderID = o2.OrderID

inner join sales.customers c3 on c3.CustomerID = o.CustomerID

WHERE o2.OrderID = o.orderid

FOR XML PATH ('OrderLines'), TYPE

DECLARE @xml varchar(1000)

DECLARE @xml_document_handle int

SET @xml = '

<Customername>Aakriti Byrraju</Customername>

</Customers>

<Customername>Bala Dixit</Customername>

</Customers>

</CustomerOrders>

-- Step 1

EXEC sp_xml_preparedocument @xml_document_handle OUTPUT, @xml;

--Step 2

SELECT *

FROM OPENXML (@xml_document_handle, '/CustomerOrders/Customers',11)

WITH ( id int,

Customername varchar(200));

--Step 3

EXEC sp_xml_removedocument @xml_document_handle

--XML output of customers, orders and order lines

SELECT c.CustomerID AS '@id'

,c.Customername

, (SELECT o.orderid AS '@OrderID'

,o.OrderDate

,(SELECT ol.orderlineId as '@OrderLineID'

,ol.Description

,ol.Quantity

FROM sales.orderlines ol

inner join sales.orders o2 on ol.OrderID = o2.OrderID

inner join sales.customers c3

on c3.CustomerID = o.CustomerID

WHERE o2.OrderID = o.orderid

for XML PATH ('OrderLines'), TYPE

)

FROM sales.customers c2

INNER JOIN sales.orders o on c2.CustomerID = o.CustomerID

WHERE c.customerID = c2.customerID

AND YEAR(OrderDate)=2013

AND MONTH(OrderDate)=1

FOR XML PATH('Orders'), ROOT('CustomerOrderId'),TYPE)

FROM sales.customers c

WHERE c.customerId in (832, 803)

ORDER BY c.CustomerName

FOR XML PATH ('Customers'), ELEMENTS, ROOT ('CustomerOrders')

DECLARE @xml varchar(max)

DECLARE @xml_document_handle int

SET @xml = '

<Customername>Aakriti Byrraju</Customername>

<Description>Ride on toy sedan car (Black) 1/12 scale</Description>

</OrderLines>

</Orders>

<Description>32 mm Double sided bubble wrap 50m</Description>

</OrderLines>

</Orders>

</CustomerOrderId>

</Customers>

<Customername>Bala Dixit</Customername>

<Description>Developer joke mug - old C developers never die (White)</Description>

</OrderLines>

<Description>USB food flash drive - chocolate bar</Description>

</OrderLines>

</Orders>

</CustomerOrderId>

</Customers>

</CustomerOrders>

-- Step 1

EXEC sp_xml_preparedocument @xml_document_handle OUTPUT, @xml;

--Step 2

SELECT *

FROM OPENXML (@xml_document_handle, '/CustomerOrders/Customers/CustomerOrderId/Orders/OrderLines',11)

WITH ( id int '../../../@id',

Customername varchar(1000) '../../../Customername',

OrderDate date '../OrderDate',

OrderID int '../@OrderID',

Description varchar(1000));

--Step 3

EXEC sp_xml_removedocument @xml_document_handle

--XQuery

SELECT @xml.query('/CustomerOrders/Customers/CustomerOrderId/Orders/OrderLines')

SELECT @xml.query('(/CustomerOrders/Customers/CustomerOrderId/Orders/OrderLines)[2]')

SELECT @xml.query('(/CustomerOrders/Customers[2]/CustomerOrderId/Orders/OrderLines)[2]')

SELECT @xml.query('(/CustomerOrders/Customers[@id=803]/CustomerOrderId/Orders/OrderLines)')

SELECT @xml.query('(/CustomerOrders/Customers[Customername="Bala Dixit"]/CustomerOrderId/Orders/OrderLines)')

--FLWOR

SELECT @xml.query('

for $Orders in /CustomerOrders/Customers/CustomerOrderId/Orders

return ($Orders)

SELECT @xml.query('

for $Orders in /CustomerOrders/Customers/CustomerOrderId/Orders

return string($Orders)

SELECT @xml.query('

for $Orders in /CustomerOrders/Customers/CustomerOrderId/Orders

let $Quantity :=$Orders/OrderLines/Quantity

where $Quantity > 20

return ($Orders)

SELECT @xml.query('

for $Orders in /CustomerOrders/Customers/CustomerOrderId/Orders

order by $Orders/@OrderID

return $Orders

--XQuery value

SELECT @xml.value('(/CustomerOrders/Customers[2]/CustomerOrderId/Orders/OrderLines)[1]', 'varchar(1000)')

SELECT @xml.value('(/CustomerOrders/Customers[2]/CustomerOrderId/Orders/OrderLines)[1]', 'int')

--XQuery exist

SELECT @xml.exist('(/CustomerOrders/Customers/CustomerOrderId/Orders/OrderLines)[5]')

SELECT @xml.exist('(/CustomerOrders/Customers[@id] = 832)')

--XQuery nodes

SELECT XML_table.value('../../../@id', N'int') as customerid

,XML_table.value('../../../Customername[1]', 'varchar(100)') as customername

,XML_table.value('../@OrderID', 'varchar(100)') as Orderid

,XML_table.value('@OrderLineID', 'varchar(100)') as OrderLineid

,XML_table.value('Quantity[1]', 'varchar(100)') as quantity

,XML_table.value('Description[1]', 'varchar(100)') as description

FROM @xml.nodes('/CustomerOrders/Customers/CustomerOrderId/Orders/OrderLines') as t(XML_table)

ORDER BY customerid desc

SELECT XML_table.value('../../@id', N'int') as customerid

,XML_table.value('@OrderID', N'int') as orderID

,XML_table.query('.') as orderdetails

FROM @xml.nodes('/CustomerOrders/Customers/CustomerOrderId/Orders') as t(XML_table)

--XQuery modify

DECLARE @xml XML

SET @xml = '

<LastName>Jackson</LastName>

</Employee>

<LastName>Didley</LastName>

</Employee>

</Employees>

SET @xml.modify('

insert attribute SSID {"idontknow"}

into (/Employees/Employee)[2]

SET @xml.modify('

insert <Employee Id="3"><FirstName>Jeff</FirstName><LastName>Williams</LastName></Employee>

after (/Employees/Employee)[2]

SET @xml.modify('

insert <Employee Id="3"><FirstName>Jeff</FirstName><LastName>Williams</LastName></Employee>

into (/Employees)[1]

--XQuery delete

SET @xml.modify('

delete /Employees/Employee[2]/@SSID

SET @xml.modify('

delete /Employees/Employee[2]/Address

If the element or attribute isn’t present, no error will be returned.

SET @xml.modify('

replace value of (/Employees/Employee[2]/@SSID)[1]

with "001-002-003"

SET @xml.modify('

replace value of (/Employees/Employee[2]/Address/text())[1]

with "Beverly Hills"

Code samples for my book on Querying data with Transact-SQL (MCSA 70-761), chapter 1

Posted on July 9, 2018 by Robert

USE WideWorldImporters

-- Create Transact-SQL SELECT queries

-- 001 
SELECT	*
FROM	Orders

-- 002
SELECT	name
FROM	sys.servers
WHERE	server_id = 0

-- 003
SELECT	*
FROM	[DESKTOP-LO5S40T].Wideworldimporters.sales.orders

-- 004
SELECT	d.name
		,MAX(b.backup_finish_date) AS 'Most recent full backup'
FROM	master.sys.databases d
		LEFT OUTER JOIN msdb..backupset b ON d.name = b.database_name
WHERE	d.name <> 'tempdb'
		AND (b.type = 'D' OR b.type IS NULL)
GROUP BY d.name
ORDER BY d.name;

-- 005
CREATE TABLE dbo.Orders (id int)

SELECT	*
FROM	dbo.Orders

DROP TABLE dbo.Orders

-- 006
SELECT name
	,default_schema_name
FROM	sys.database_principals
WHERE	principal_id = user_id();

-- 007
CREATE SYNONYM [dbo].[Orders] FOR [WideWorldImporters].[Sales].[Orders]
SELECT	*
FROM	dbo.Orders

-- 008
DROP SYNONYM [dbo].[Orders]

-- 009
SELECT	master.sys.databases.name

-- 010
SELECT	o.*
FROM	(SELECT * FROM Sales.Orders) o

-- SELECT clause

-- 011
SELECT	OrderID as 'Order number'
FROM	Sales.Orders

SELECT	'Order number' =  OrderID
FROM	Sales.Orders

-- 012
SELECT	UPPER(FullName)
FROM	[Application].[People]

--WHERE clause

-- 013
SELECT	*
FROM	[Application].[People]
WHERE	PersonID = 1

-- 014
SELECT	*
FROM	[Application].[People]
WHERE	FullName = 'Kayla Woodcock'

-- 015
SELECT	*
FROM	[Application].[People]
WHERE	EmailAddress = NULL

-- 016
SELECT	*
FROM	[Application].[People]
WHERE	EmailAddress IS NULL

-- 017
SELECT	*
FROM	[Application].[People]
WHERE	FullName LIKE 'Daniel%'

-- 018
SELECT	*
FROM	[Application].[People]
WHERE	PreferredName LIKE 'Isabell_'

-- 019
SELECT	*
FROM	[Application].[People]
WHERE	PreferredName LIKE 'Isabell[a-z]'

-- 020
SELECT	*
FROM	[Application].[People]
WHERE	PreferredName IN ('Isabelle', 'Isabell')

-- 021
SELECT	*
FROM	[Application].[People]
WHERE	PreferredName IN (	SELECT	CustomerName
				FROM	sales.Customers )

-- 022
SELECT	*
FROM	[Application].[People]
WHERE	PreferredName BETWEEN 'I' AND 'Isabelle'

-- 023
SELECT	*
FROM	[Application].[People]
WHERE	PersonID BETWEEN 1 AND 10

-- 024
SELECT GETDATE()

-- 025
SELECT	*
FROM	[Application].[People]
WHERE	ValidTo > GETDATE()

-- 026
SELECT LEFT('Isabelle', 3)

-- 027
SELECT	*
FROM	[Application].[People]
WHERE	LEFT(PreferredName,3) = 'Isa' 

SELECT	*
FROM	[Application].[People]
WHERE	PreferredName LIKE 'Isa%' 

-- 028
DECLARE @FirstName varchar(50)

SET @FirstName = 'Isabelle'

SELECT	*
FROM	[Application].[People]
WHERE	PreferredName = @FirstName 

SELECT	*
FROM	[Application].[People]
WHERE	PreferredName = 'Isabelle'

-- 029
DECLARE @FullName varchar(50)

SELECT	@FullName = FullName
FROM	[Application].[People]
WHERE	PreferredName = 'Isabelle'

SELECT @FullName

-- 030
SELECT	*
FROM	[Application].[People]
WHERE	1 = 1

-- 031
SELECT	*
FROM	[Application].[People]
WHERE	PersonID = 1
		AND PersonID = 2

-- 032
SELECT	*
FROM	[Application].[People]
WHERE	PersonID = 1
		OR PersonID = 2

--033
SELECT	*
FROM	[Application].[People]
WHERE	PersonID IN (1, 2)

-- 034
SELECT	*
FROM	[Application].[People]
WHERE	(PersonID = 1
		OR PersonID = 2)
		AND PreferredName = 'Isabella'

SELECT	*
FROM	[Application].[People]
WHERE	PersonID = 1
		OR (PersonID = 2
		AND PreferredName = 'Isabella')

/* ORDER BY clause */

-- 035
SELECT	*
FROM	[Application].[People]
ORDER BY PreferredName

-- 036
SELECT	*
FROM	[Application].[People]
ORDER BY PreferredName DESC

-- 037
SELECT	*
FROM	[Application].[People]
ORDER BY PreferredName, PersonID

-- 038
SELECT	PreferredName
FROM	[Application].[People]
ORDER BY ValidFrom


/* Set operators */

-- 039
SELECT 1, 'record 1'
UNION
SELECT 2, 'record 2'

-- 040
SELECT 1, 'record 1'
UNION
SELECT 1, 'record 2'

SELECT 1, 'record 1'
UNION ALL
SELECT 1, 'record 2'

-- 041
SELECT 1, 'record 1' as Alias1
UNION
SELECT 2 as Alias2, 'record 2' as Alias3

-- 042 
SELECT 1, 'record 1' 
UNION 
SELECT 2 , GETDATE()

-- 043
SELECT 1, 'record 1'
EXCEPT
SELECT 1, 'record 1'

-- 044
SELECT 1, 'record 1'
INTERSECT
SELECT 1, 'record 1'

-- 045
USE TestDB
GO
CREATE TABLE dbo.Customers 
	(
	CustomerID	tinyint			NOT NULL	IDENTITY
	,FirstName	varchar(100)	NOT NULL
	,LastName	varchar(100)	NOT NULL
	,[Address]	varchar(100)	NOT NULL
	);

-- 046
CREATE TABLE dbo.Employees 
	(
	EmployeeID	tinyint			NOT NULL	IDENTITY
	,FirstName	varchar(100)	NOT NULL
	,LastName	varchar(100)	NOT NULL
	,[Address]	varchar(100)	NOT NULL
	);

-- 047
INSERT dbo.Customers VALUES ('Bob', 'Jackson', 'Main street 1, Dallas');
INSERT dbo.Customers VALUES ('Frank', 'Smith', 'Second street 2, Miami');
INSERT dbo.Customers VALUES ('Joe', 'Johnson', 'Third Avenue 3, New York');

INSERT dbo.Employees VALUES ('Jack', 'Ford', 'Second street 2, Denver');
INSERT dbo.Employees VALUES ('Donald', 'Charleston', 'Times Square, New York');
INSERT dbo.Employees VALUES ('Bob', 'Jackson', 'Main street 1, Dallas');

-- 048
SELECT	FirstName, LastName, Address
FROM	Customers
UNION 
SELECT	FirstName, LastName, Address
FROM	Employees

-- 049
DROP TABLE dbo.Customers;
DROP TABLE dbo.Employees;

/* Section 2: Querying multiple tables by using joins */

-- 050
SELECT	*
FROM	Sales.Orders
	,Sales.OrderLines

-- 051
SELECT	*
FROM	Sales.Orders
	CROSS JOIN Sales.OrderLines

-- 052
SELECT	*
FROM	Sales.Orders
	,Sales.OrderLines
WHERE	Sales.Orders.OrderID = Sales.OrderLines.OrderID

-- 053
SELECT	*
FROM	Sales.Orders o
	,Sales.OrderLines ol
WHERE	o.OrderID = ol.OrderID

-- 054
SELECT	*
FROM	Sales.Orders o
	,Sales.OrderLines ol
WHERE	o.OrderID = ol.OrderID
	AND o.OrderDate = '2014-07-17'

-- 055
SELECT	*
FROM	Sales.Orders o
	JOIN Sales.OrderLines ol ON o.OrderID = ol.OrderID
WHERE	o.OrderDate = '2014-07-17'

-- 056
SELECT	*
FROM	warehouse.StockItems
WHERE	StockItemID NOT IN (	SELECT	StockItemID 
				FROM	sales.Orderlines)


-- 057
CREATE TABLE dbo.Customers 
	(
	CustomerID	tinyint			NOT NULL	IDENTITY PRIMARY KEY
	,FirstName	varchar(100)	NOT NULL
	,LastName	varchar(100)	NOT NULL
	,[Address]	varchar(100)	NOT NULL
	);

CREATE TABLE dbo.Orders 
	(
	OrderID			tinyint			NOT NULL	IDENTITY PRIMARY KEY
	,CustomerID		tinyint			NOT NULL
	,OrderDate		datetime		NOT NULL
	,SalesAmount	decimal(18,2)	NOT NULL
	);

INSERT dbo.Customers VALUES ('Bob', 'Jackson', 'Main street 1, Dallas');
INSERT dbo.Customers VALUES ('Frank', 'Smith', 'Second street 2, Miami');
INSERT dbo.Customers VALUES ('Joe', 'Johnson', 'Third Avenue 3, New York');

INSERT dbo.Orders VALUES (1, '2011-01-01', 30.02);
INSERT dbo.Orders VALUES (2, '2012-02-02', 15.99);
INSERT dbo.Orders VALUES (4, '2014-04-04', 107.00);

-- 058
SELECT	*
FROM	dbo.Customers c
	LEFT OUTER JOIN dbo.Orders o ON c.CustomerID = o.CustomerID

-- 059
SELECT	*
FROM	dbo.Customers c
	RIGHT OUTER JOIN dbo.Orders o ON c.CustomerID = o.CustomerID

-- 060
INSERT dbo.Orders VALUES (1, '2015-05-05', 230.02);

-- 061 
SELECT * 
FROM   dbo.Customers c 
       FULL OUTER JOIN dbo.Orders o ON c.CustomerID = o.CustomerID

-- 062
CREATE TABLE dbo.OrderLines 
	(
	OrderLineID	tinyint			NOT NULL
	,OrderID	tinyint			NOT NULL	
	,Product	varchar(100)	NOT NULL
	,Units		tinyint			NOT NULL
	,UnitPrice	decimal(18,2)	NOT NULL
	);

INSERT dbo.OrderLines VALUES (1, 1, 'ProductA', 1, 10.04);
INSERT dbo.OrderLines VALUES (2, 1, 'ProductB', 2, 9.99);

-- 063
SELECT	*
FROM	dbo.Customers c
	INNER JOIN dbo.Orders o ON c.CustomerID = o.CustomerID
	LEFT OUTER JOIN dbo.OrderLines ol on ol.OrderID = o.OrderID;

-- 064
SELECT	c.FirstName
		,c.LastName
		,o.OrderDate
		,o.SalesAmount
		,ol.Product
		,ol.Units
		,ol.UnitPrice
FROM	dbo.Customers c
		INNER JOIN dbo.Orders o ON c.CustomerID = o.CustomerID
		LEFT OUTER JOIN dbo.OrderLines ol on ol.OrderID = o.OrderID
ORDER BY c.CustomerID, o.OrderID, ol.OrderLineID;

-- 065
DROP TABLE dbo.Customers;
DROP TABLE dbo.Orders;
DROP TABLE dbo.OrderLines;

--  Construct multiple JOIN operators using AND and OR

-- 066
CREATE TABLE dbo.Customers 
	(
	FirstName	varchar(100)	NOT NULL
	,LastName	varchar(100)	NOT NULL
	,[Address]	varchar(100)	NOT NULL
	);

ALTER TABLE dbo.Customers ADD CONSTRAINT PK_Customers
PRIMARY KEY (FirstName, LastName)
GO

CREATE TABLE dbo.Orders 
	(
	OrderID	tinyint	NOT NULL	IDENTITY PRIMARY KEY
	,FirstName	varchar(100)	NOT NULL
	,LastName	varchar(100)	NOT NULL
	,OrderDate	datetime	NOT NULL
	,SalesAmount	decimal(18,2)	NOT NULL
	);

INSERT dbo.Customers VALUES ('Bob', 'Jackson', 'Main street 1, Dallas');
INSERT dbo.Customers VALUES ('Frank', 'Smith', 'Second street 2, Miami');
INSERT dbo.Customers VALUES ('Joe', 'Johnson', 'Third Avenue 3, New York');

INSERT dbo.Orders VALUES ('Bob', 'Jackson', '2011-01-01', 30.02);
INSERT dbo.Orders VALUES ('Frank', 'Smith', '2012-02-02', 15.99);
INSERT dbo.Orders VALUES ('Bob', 'Smith', '2014-04-04', 107.00);

-- 067
SELECT	*
FROM	dbo.Customers c
	FULL OUTER JOIN dbo.Orders o 
ON c.FirstName = o.FirstName AND c.LastName = o.LastName

-- 068
DROP TABLE dbo.Customers;
DROP TABLE dbo.Orders; 

-- 069
CREATE TABLE dbo.Student 
	(
	CustomerID	tinyint	NOT NULL	IDENTITY PRIMARY KEY
	,FirstName	varchar(100)	NOT NULL
	,LastName	varchar(100)	NOT NULL
	,FatherID	tinyint	NOT NULL
	,MotherID	tinyint	NOT NULL
	,IsCurrent	bit		NOT NULL
	);

CREATE TABLE dbo.Parent 
	(
	ParentID	tinyint	NOT NULL	IDENTITY PRIMARY KEY
	,FirstName	varchar(100)	NOT NULL
	,LastName	varchar(100)	NOT NULL
	,EmailAddress	varchar(100)	NULL
	);

INSERT dbo.Student VALUES ('Bob jr', 'Jackson', 1,2, 0);
INSERT dbo.Student VALUES ('Joe jr', 'Johnson', 3,4, 1);

INSERT dbo.Parent VALUES ('Bob sr', 'Jackson', NULL);
INSERT dbo.Parent VALUES ('Betty', 'Jackson', 'bettyjackson@someprovider.com');
INSERT dbo.Parent VALUES ('Joe sr', 'Johnson', 'joejohnson@someprovider.com');
INSERT dbo.Parent VALUES ('Jane', 'Johnson', 'janejohnson@someprovider.com');

-- 070
SELECT	s.FirstName AS 'Student first name'
		,s.LastName AS 'Student last name'
		,p.FirstName AS 'Parent first name'
		,p.LastName AS 'Parent last name'
		,p.EmailAddress
FROM	dbo.Student s
		inner join Parent p on s.FatherID = p.ParentID OR s.MotherID = p.ParentID
WHERE	s.IsCurrent = 1

-- 071
DROP TABLE dbo.Student
DROP TABLE dbo.Parent


-- Write queries with NULLs on joins

-- 072
CREATE TABLE dbo.Customers 
	(
	CustomerID	tinyint	NULL	
	,FirstName	varchar(100)	NOT NULL
	,LastName	varchar(100)	NOT NULL
	,[Address]	varchar(100)	NOT NULL
	);

CREATE TABLE dbo.Orders 
	(
	OrderID	tinyint	NOT NULL	IDENTITY PRIMARY KEY
	,CustomerID	tinyint	NULL
	,OrderDate	datetime	NOT NULL
	,SalesAmount	decimal(18,2)	NOT NULL
	);

INSERT dbo.Customers VALUES (1, 'Bob', 'Jackson', 'Main street 1, Dallas');
INSERT dbo.Customers VALUES (2, 'Frank', 'Smith', 'Second street 2, Miami');
INSERT dbo.Customers VALUES (NULL, 'Joe', 'Johnson', 'Third Avenue 3, New York');

INSERT dbo.Orders VALUES (1, '2011-01-01', 30.02);
INSERT dbo.Orders VALUES (2, '2012-02-02', 15.99);
INSERT dbo.Orders VALUES (NULL, '2014-04-04', 107.00);

-- 073
SELECT * 
FROM dbo.Customers c 
INNER JOIN dbo.Orders o ON c.CustomerID = o.CustomerID 

-- 074
SELECT	ISNULL(CustomerID, 99)
FROM	dbo.Customers

-- 075
SELECT	*
FROM	dbo.Customers c
	INNER JOIN dbo.Orders o ON ISNULL(c.CustomerID,99) = ISNULL(o.CustomerID,99)

-- 076
SELECT	*
FROM	dbo.Customers c
	INNER JOIN dbo.Orders o ON	(c.CustomerID IS NULL and o.CustomerID IS NULL)
	OR c.CustomerID = o.CustomerID

-- 077
DROP TABLE dbo.Customers;
DROP TABLE dbo.Orders; 

/* Implement functions and aggregate data */

-- 078
SELECT	UPPER(FullName)
FROM	[Application].[People]

-- 079
SELECT LOWER('ABCDE')

-- 080
SELECT UPPER(LOWER('ABCDE'))

-- 081
SELECT	*
FROM	[Application].[People]
WHERE	LOWER(PreferredName) = 'isabelle'

-- 082
SELECT *  
FROM fn_virtualfilestats(NULL,NULL); 

-- 083
SELECT DB_ID('WideWorldImporters')

-- 084
SELECT	DB_NAME(vfs.Dbid) as 'Database'
	,mf.name as 'File name'
	,mf.physical_name
	,CASE NumberReads
		WHEN 0 THEN 'none'
			ELSE CAST(IoStallReadMS/NumberReads AS varchar(100))
		END as 'Read latency'
	,CASE NumberWrites
		WHEN 0 THEN 'none'
			ELSE CAST(IoStallWriteMS/NumberWrites AS varchar(100))
		END as 'Write latency'  
FROM	fn_virtualfilestats(NULL,NULL) vfs
	INNER JOIN sys.master_files mf ON vfs.DbId = mf.database_id AND vfs.Fileid = mf.file_id
ORDER BY DbId, file_id;

/* Identify the impact of function usage to query performance and WHERE clause sargability */

-- 085
SELECT	PreferredName 
FROM	[Application].[People]
WHERE	LEFT(PreferredName,3) = 'Isa'

SELECT	PreferredName 
FROM	[Application].[People]
WHERE	PreferredName LIKE 'Isa%'

/* index hint CREATE NONCLUSTERED INDEX [<Name of Missing Index, sysname,>] ON [Application].[People] ([PreferredName]) */

-- 086
CREATE NONCLUSTERED INDEX [NonClusteredIndex-PerformanceDemo] ON [Application].[People]
(
	[PreferredName] ASC
)

GO

-- 087
DROP INDEX [NonClusteredIndex-PerformanceDemo] ON [Application].[People]

-- 088
SELECT DATEADD(week, 1, '2017-08-25')

-- 089
SELECT DATEADD(day, -1, GETDATE())

-- 090
CREATE NONCLUSTERED INDEX [NCIX-ExpectedDeliveryDate] ON [Sales].[Orders] ( [ExpectedDeliveryDate] ASC ) 

-- 091
SELECT	OrderID
FROM	Sales.Orders
WHERE	ExpectedDeliveryDate = DATEADD(day, 1, GETDATE())

SELECT	OrderID
FROM	Sales.Orders
WHERE	GETDATE() = DATEADD(day, -1, ExpectedDeliveryDate)

-- 092
DECLARE @tomorrow date

SET @tomorrow = DATEADD(day, 1, GETDATE())

SELECT	OrderID
FROM	Sales.Orders
WHERE	ExpectedDeliveryDate = @tomorrow

-- 093
DROP INDEX [NCIX-ExpectedDeliveryDate] ON [Sales].[Orders]

/* Identify the differences between deterministic and non-deterministic functions */

-- 094
select RAND()

/* Use built-in aggregate functions */

-- 095
SELECT	MAX(preferredname)
FROM	Application.People

-- 096
SELECT	TOP 1 PreferredName
FROM	Application.People
ORDER BY PreferredName DESC

-- 097
SELECT	count(*)
FROM	sales.orders

-- 098
EXEC sp_spaceused 'sales.orders'

-- 099
SELECT	SalespersonPersonID
		,count(*) AS 'Orders per salesperson'
FROM	sales.orders
GROUP BY SalespersonPersonID
ORDER BY SalespersonPersonID

-- 100
SELECT	'Average' = AVG(quantity)
		,'Average #2' = AVG(CAST(quantity as decimal(5,2)))
		,'Number' = COUNT(*)
		,'Maximum' = MAX(quantity)
		,'Minimum' = MIN(quantity)
		,'Total' = SUM(quantity)
FROM Sales.Orderlines;

-- 101
SELECT cast(9310904 as dec(18,2))/cast(231412 as dec(18,2))
SELECT 9310904/231412

/* Use arithmetic functions, date-related functions, and system functions */

-- 102
SELECT	'Year' = YEAR('2017-08-26')
		,'Year #2' = DATEPART(YEAR,'2017-08-26') 
		,'Month' =  MONTH('2017-08-26')
		,'Name of the month' = DATENAME(MONTH,'2017-08-26')
		,'Day' =  DAY('2017-08-26')
		,'Name of the day' = DATENAME(WEEKDAY,'2017-08-26')
		,'Day of the week' = DATEPART(WEEKDAY,'2017-08-26');

-- 103
SELECT @@DATEFIRST

-- 104
SET DATEFIRST 1;
SELECT 'First day of the week' = CASE @@DATEFIRST
	WHEN 1 THEN 'Monday'
	WHEN 2 THEN 'Tuesday'
	WHEN 3 THEN 'Wednesday'
	WHEN 4 THEN 'Thursday'
	WHEN 5 THEN 'Friday'
	WHEN 6 THEN 'Saturday'
	WHEN 7 THEN 'Sunday'
	ELSE 'I do not know what went wrong here'
	END
SET DATEFIRST 7;

-- 105
SELECT 'Current time' = Current_Timestamp
		,'Current time #2' = GETDATE()
		,'Current time more precision' = Sysdatetime()
SELECT 'Current UTC time' = Getutcdate()
		,'Current time more precision' = Sysutcdatetime()
		,'Current time + UTC offset' = Sysdatetimeoffset()

-- 106
SELECT TODATETIMEOFFSET(GETDATE(), '+00:00')

-- 107
SELECT 'Moscow time' = SWITCHOFFSET (Sysdatetimeoffset(), '+03:00')

-- 108
SELECT ISDATE('2017-02-29')

-- 109
SELECT DATEDIFF(day,'1971-09-03', GETDATE())


/* arithmetic functions */

-- 110
SELECT ABS (7), ABS(-7)	
 
-- 111
SELECT 7 % 3

-- 112
SELECT	'Floor' =			FLOOR(12.345)
		,'Ceiling' =		CEILING(12.345)
		,'Round to 100' =	ROUND(12.345, -2)
		,'Round to 10' =	ROUND(12.345, -1)
		,'Round to 1' =		ROUND(12.345, 0)
		,'Round to .1' =	ROUND(12.345, 1)
		,'Round to .01' =	ROUND(12.345, 2)

/* string functions */

-- 113
SELECT CONCAT('mon', 'day')

-- 114
SELECT 'mon' + 'day'

-- 115
SELECT	firstname + ' ' + lastname
FROM	dbo.parent

SELECT	CONCAT(firstname, ' ', lastname)
FROM	dbo.parent

-- 116
SET CONCAT_NULL_YIELDS_NULL OFF
SELECT 'mon' + NULL + 'day'
SELECT CONCAT('mon', NULL, 'day')

SET CONCAT_NULL_YIELDS_NULL ON
SELECT 'mon' + NULL + 'day'
SELECT CONCAT('mon', NULL, 'day')

-- 117
SELECT LEFT('monday',3)
SELECT RIGHT('monday',3)

-- 118
SELECT SUBSTRING('The middle part', 5, 6)

-- 119
SELECT LEFT('monday', 3)

-- 120
SELECT SUBSTRING('monday', 1, 3)

-- 121
SELECT CHARINDEX('middle', 'the middle part')

-- 122
SELECT CHARINDEX('t', 'the middle part')

-- 123
SELECT CHARINDEX('t', 'the middle part', 2)

-- 124
SELECT PATINDEX('%m%e%', 'the middle part')  

-- 125
SELECT REPLACE('the middle part', 'middle', 'best')

-- 126
SELECT LEN('the middle part')

-- 127
SELECT CHAR(65)
SELECT ASCII('A')

-- 128
DECLARE @strange_string VARCHAR(100) 

SET @strange_string = 'mon' + CHAR(27) + 'day'
SELECT @strange_string

SELECT ASCII(SUBSTRING(@strange_string,4,1))

-- 129
BACKUP DATABASE model TO DISK = 'd:\model.bak'

-- 130
SELECT	'BACKUP DATABASE ' + name 
FROM	sys.databases
WHERE	name <> 'tempdb'

-- 131
BACKUP DATABASE master
BACKUP DATABASE model
BACKUP DATABASE msdb
BACKUP DATABASE TestDB
BACKUP DATABASE WideWorldImporters

-- 132
SELECT	'BACKUP DATABASE ' + name + ' TO DISK = D:\' + name + '.bak'

-- 133
SELECT	'BACKUP DATABASE ' + name + ' TO DISK = ''D:\' + name + '.bak'''

-- 134
SELECT	'BACKUP DATABASE ' + name + 
' TO DISK = ' + CHAR(39) + 'D:\' + name + '.bak' + CHAR(39)

-- 135
SELECT	CONCAT('BACKUP DATABASE ', name, 
' TO DISK = ', CHAR(39), 'D:\', name, '.bak', CHAR(39))

-- 136
SELECT REVERSE('monday')

/* system functions */

-- 136
SELECT HOST_NAME()

-- 137
SELECT USER_NAME()

-- 138
CREATE TABLE dbo.Employees 
	(
	EmployeeID	tinyint	NOT NULL	IDENTITY
	,FirstName	varchar(100)	NOT NULL
	,LastName	varchar(100)	NOT NULL
	,[Address]	varchar(100)	NOT NULL
	);

-- 139 
INSERT dbo.Employees VALUES ('Jack', 'Ford', 'Second street 2, Denver');

-- 140
INSERT dbo.Employees VALUES (1, 'Jack', 'Ford', 'Second street 2, Denver');

-- 141
SET IDENTITY_INSERT dbo.Employees ON;
INSERT dbo.Employees (EmployeeID, FirstName, LastName, Address)
VALUES (1, 'Donald', 'Charleston', 'Times Square, New York');
SET IDENTITY_INSERT dbo.Employees OFF;

-- 142
INSERT dbo.Empolyees (FirstName, LastName, Address)
VALUES ('A.', 'Snowman' 'Mount Everest, Nepal');
SELECT @@IDENTITY

-- 143
DROP TABLE IF EXISTS dbo.Orders
DROP TABLE IF EXISTS dbo.OrderLines

CREATE TABLE dbo.Orders 
	(
	OrderID	tinyint	NOT NULL	IDENTITY PRIMARY KEY
	,CustomerID	tinyint	NOT NULL
	,OrderDate	datetime	NOT NULL
	,SalesAmount	decimal(18,2)	NOT NULL
	);

CREATE TABLE dbo.OrderLines 
	(
	OrderLineID	tinyint	NOT NULL	IDENTITY PRIMARY KEY
	,OrderID	tinyint	NOT NULL	
	,Product	varchar(100)	NOT NULL
	,Units		tinyint	NOT NULL
	,UnitPrice	decimal(18,2)	NOT NULL
	);

DECLARE @OrderID tinyint
INSERT dbo.Orders VALUES (1,'2015-05-05', 230.02);
SELECT @OrderID = @@IDENTITY

INSERT dbo.OrderLines VALUES ( @OrderID, 'ProductA', 1, 10.04);

-- 144
/*Old syntax to drop a table only if it exists*/
IF EXISTS (	SELECT name 
FROM 	sys.tables 
WHERE 	name = 'Orders' 
and schema_id=SCHEMA_ID('dbo'))
DROP TABLE dbo.Orders

-- 145
SELECT IDENT_CURRENT('dbo.Orders')

-- 146
SELECT 'Globally unique identifier' = NEWID()

-- 147
CREATE TABLE tblGUID (
	id	uniqueidentifier DEFAULT NEWSEQUENTIALID()
	,text	varchar(100));

INSERT tblGUID (text) VALUES ('One')
INSERT tblGUID (text) VALUES ('Two')
INSERT tblGUID (text) VALUES ('Three')

SELECT *
FROM tblGUID

-- 148
SELECT	ISNUMERIC('12') as Number
	,ISNUMERIC(12) as Number
	,ISNUMERIC('12A') as Number

-- 149
SELECT	TRY_CAST('$20' as money)
SELECT	TRY_CAST('$20' as int)
SELECT	CAST('$20' as int)

-- 150
SELECT	CAST('20170914' AS datetime)
	,CONVERT(datetime, '20170914')

-- 151
SELECT	 CONVERT(varchar(100), GETDATE(), 100) AS 'Default'
	,CONVERT(varchar(100), GETDATE(), 101) AS 'US'
	,CONVERT(varchar(100), GETDATE(), 1) AS 'US (without century)'
	,CONVERT(varchar(100), GETDATE(), 126) AS 'ISO8601'
	,CONVERT(varchar(100), GETDATE(), 113) AS 'Europe default'

-- 152
SELECT	*
FROM	[Sales].[Invoices]

SELECT @@ROWCOUNT AS 'Number of records affected'

-- 153
SELECT * 
FROM [Sales].[Invoices] 

SELECT ROWCOUNT_BIG() AS 'Number of records affected'

/* Modify data */

-- 154
DROP IF EXISTS TABLE dbo.Employees 

CREATE TABLE dbo.Employees 
	(
	EmployeeID	tinyint	NOT NULL	IDENTITY
	,FirstName	varchar(100)	NOT NULL
	,LastName	varchar(100)	NOT NULL
	,[Address]	varchar(100)	NOT NULL
	);

INSERT dbo.Customers VALUES ('Bob', 'Jackson', 'Main street 1, Dallas');

-- 155
INSERT dbo.Employees (FirstName, LastName) 
VALUES ('Bob', 'Jackson')

INSERT dbo.Employees (FirstName, LastName, Address) 
VALUES ('Bob', 'Jackson', NULL)

-- 156
CREATE TABLE dbo.Employees 
	(
	EmployeeID	tinyint	NOT NULL IDENTITY
	,FirstName	varchar(100)	NOT NULL
	,LastName	varchar(100)	NOT NULL
	,[Address]	varchar(100)	NOT NULL DEFAULT 'Under the bridge'
	)

-- 157
ALTER TABLE dbo.Employees ADD DEFAULT ('Under the bridge') FOR [Address]

INSERT dbo.Employees (FirstName, LastName) 
VALUES ('Bob', 'Jackson')

-- 158
INSERT dbo.Employees (FirstName, LastName) 
VALUES ('Bob', 'Jackson') 

INSERT dbo.Employees (FirstName, LastName, Address) 
VALUES ('Bob', 'Jackson', DEFAULT)

-- 159
INSERT dbo.Employees DEFAULT VALUES

-- 160
INSERT  dbo.Employees (FirstName, LastName) 
VALUES	('Bob', 'Jackson')
	,('Bo', 'Jackson')
	,('Bill', 'Jackson')

-- 161
DROP TABLE IF EXISTS dbo.Employees_backup

CREATE TABLE dbo.Employees_backup 
	(
	FirstName	varchar(100)	NOT NULL
	,LastName	varchar(100)	NOT NULL
	,[Address]	varchar(100)	NOT NULL
	)

INSERT	dbo.Employees_backup
SELECT	FirstName, LastName, [Address]
FROM	dbo.Employees

-- 162
INSERT	dbo.Employees_backup
SELECT	FirstName, LastName, [Address]
FROM	dbo.Employees
UNION 
SELECT 'Tim', 'Smith', 'Miami'

-- 163
DROP TABLE IF EXISTS dbo.Employees_backup

SELECT	FirstName, LastName, [Address]
INTO	dbo.Employees_backup
FROM	dbo.Employees

-- 164
CREATE PROC dbo.usp_get_employees
AS
BEGIN
	SELECT FirstName, LastName, Address FROM dbo.Employees
END

-- 165
EXEC usp_get_employees
 
-- 166
INSERT 	dbo.Employees_backup
EXEC 	usp_get_employees

-- 167
DECLARE @sql nvarchar(1000)

SET @sql = 'SELECT FirstName, LastName, Address FROM dbo.Employees'

EXEC (@sql)

-- 168
EXEC sp_executesql @statement = @sql

-- 169
INSERT dbo.Employees_backup
EXEC (@sql)

-- 170
INSERT dbo.Employees_backup
EXEC sp_executesql @statement = @sql

/* In more detail: dynamic SQL */

-- 171
SELECT	TOP (3) *
FROM	dbo.Employees

-- 172
SELECT	TOP 50 percent *
FROM	dbo.Employees

-- 173
SELECT	TOP 50 percent *
FROM	dbo.Employees
ORDER BY LastName

-- 174
DECLARE @sql	varchar(1000)
	,@top	int

SET @top = 3
SET @sql = 'SELECT TOP ' + CAST (@top as varchar(10)) + 'FirstName, LastName, Address FROM dbo.Employees'

EXEC (@sql)

-- 175
-- create the table 
CREATE TABLE Students (
FirstName	varchar(100)
	,LastName	varchar(100))

INSERT INTO dbo.Students (FirstName, LastName) VALUES('Robert', 'Tables')

-- fetch the student record 
DECLARE @sql		nvarchar(1000)
	,@Firstname	nvarchar(1000)

SET @Firstname = 'Robert'
SET @sql = 'SELECT * FROM dbo.Students WHERE FirstName = ' + CHAR(39) + @Firstname + CHAR(39)

EXEC (@sql)

-- 176
SET @Firstname = 'Robert''; DROP TABLE dbo.Students--'

-- 177
SET @sql = 'SELECT * FROM dbo.Students WHERE FirstName = @FirstName' 

EXECUTE sp_executesql 
	@statement = @sql
	,@parameters = N'@FirstName as varchar(1000)'
	,@FirstName = @FirstName

-- 178
DECLARE @sql nvarchar(1000)
	,@top int

SET @sql = 'SELECT TOP (@top) FirstName, LastName, Address FROM dbo.Employees'
SET @top = 3

EXEC sp_executesql 
	@statement = @sql
	,@parameters = N'@top as int'
	,@top = @top

-- 179
SELECT TOP (@top) FirstName, LastName, Address 
FROM dbo.Employees

/* Cursors */

-- 180
USE WideWorldImporters

DECLARE crsLoop CURSOR FOR
SELECT	TOP (50) FullName, UserPreferences
FROM	[Application].[People]
ORDER BY FullName

DECLARE @FullName nvarchar(50)
	,@UserPreferences nvarchar(max)

OPEN crsLoop 

FETCH NEXT FROM crsLoop INTO @FullName, @UserPreferences

WHILE @@FETCH_STATUS = 0
BEGIN
	SELECT @FullName AS [Full Name], @UserPreferences AS [User Preferences]
	FETCH NEXT FROM crsLoop INTO @FullName, @UserPreferences
END

CLOSE crsLoop
DEALLOCATE crsLoop

-- 181
SELECT @@SPID

-- 182
KILL 58

-- 183
SELECT	*
FROM	master..sysprocesses
WHERE	dbid= DB_ID('TestDB')

-- 184
SELECT	spid
FROM	master..sysprocesses
WHERE	dbid= DB_ID('TestDB')
GROUP BY spid

SELECT	DISTINCT spid
FROM	master..sysprocesses
WHERE	dbid= DB_ID('TestDB')

-- 185
SELECT	'KILL ' + CAST(spid AS VARCHAR(10))

-- 186
DECLARE @SQL NVARCHAR(100);

DECLARE crsKill CURSOR LOCAL FAST_FORWARD
FOR SELECT	'KILL ' + CAST(spid AS VARCHAR(10))
    FROM	master.dbo.sysprocesses   
    WHERE	dbid = DB_ID('TestDB')
    GROUP BY spid;

OPEN crsKill;

FETCH crsKill INTO @SQL;

WHILE @@FETCH_STATUS = 0
BEGIN
    EXEC sp_executesql @SQL;

    FETCH crsKill INTO @SQL
END;

CLOSE crsKill;
DEALLOCATE crsKill;

/* update */

-- 187
UPDATE	dbo.Employees
SET	LastName = 'Didley'
WHERE	FirstName = 'Bo'

-- 188
UPDATE	TOP (1) dbo.Employees
SET	LastName = 'Didley'
WHERE	FirstName = 'Bo'
ORDER BY EmployeeID

-- 189
UPDATE	dbo.Employees
SET	LastName = 'Didley'
FROM	(	SELECT	TOP (1) EmployeeID
		FROM	dbo.Employees
		WHERE	FirstName = 'Bo'
		ORDER BY EmployeeID) AS e
WHERE	e.EmployeeID = Employees.EmployeeID

-- 190
UPDATE dbo.Employees
SET	LastName = LTRIM(RTRIM(LastName))
	,Address = DEFAULT
WHERE	FirstName = 'Bo'

-- 191
UPDATE dbo.Employees
SET	LastName = LTRIM(RTRIM(LastName))
	,Address = 'Home of mr. ' + FirstName + ' ' + LastName
WHERE	FirstName = 'Bo'

-- 192
ALTER TABLE dbo.Employees ADD Salary decimal(18,2) DEFAULT 1000.00

UPDATE	dbo.Employees
SET	Salary = DEFAULT

-- 193
UPDATE dbo.Employees
SET	Salary = Salary + 100
WHERE	FirstName = 'Bo'

UPDATE dbo.Employees
SET	Salary +=  100
WHERE	FirstName = 'Bo'


-- 194
-- Bitwise comparison operators
SELECT 1 & 1 AS 'Two ones', 1 & 0 AS 'Left one', 0 & 1  AS 'Right one', 0 & 0 AS 'No one'
SELECT 1 | 1 AS 'Two ones', 1 | 0 AS 'Left one', 0 | 1 AS 'Right one', 0 | 0 AS 'No one'
SELECT 1 ^ 1 AS 'Two ones', 1 ^ 0 AS 'Left one', 0 ^ 1 AS 'Right one', 0 ^ 0 AS 'No one'

-- 195
SELECT 5 & 19, 5 | 19, 5 ^ 19

-- 196
-- Update on join
UPDATE	c
SET	c.StandardDiscountPercentage = 5
FROM	sales.customers c
	INNER JOIN sales.Orders o on c.CustomerID = o.CustomerID
WHERE	o.OrderDate > '2016-01-01'

-- 197
UPDATE	Sales.Customers
SET	StandardDiscountPercentage = 0
WHERE	StandardDiscountPercentage = 5

-- 198
-- Nondeterministic update on join
UPDATE	o
SET	comments = ol.Description
FROM	sales.orders o
	INNER JOIN sales.orderlines ol ON o.orderid = ol.orderid
WHERE	o.OrderID = 46

-- 199
UPDATE	Sales.Orders
SET		comments = NULL

-- 200
-- Update WHERE CURRENT OF
DECLARE crsOrders CURSOR FOR
SELECT	orderid
FROM	Sales.orders

DECLARE @orderid int

OPEN crsOrders

FETCH NEXT FROM crsOrders INTO @orderid

WHILE @@FETCH_STATUS = 0
BEGIN
	UPDATE Sales.Orders
	SET	Comments = 'This is order ' + CAST(@orderid AS VARCHAR(10))
	WHERE CURRENT OF crsOrders

	FETCH NEXT FROM crsOrders INTO @orderid
END

CLOSE crsOrders
DEALLOCATE crsOrders

-- 201
UPDATE	Sales.Orders
SET	Comments = 'This is order ' + CAST(OrderId as varchar(10))

-- 202
UPDATE	Sales.Orders
SET	comments = NULL

-- 203
DECLARE @Comments nvarchar(max)

UPDATE	Sales.Orders
SET	@Comments = Comments = 'This is order ' + CAST (OrderId as varchar(10))
WHERE	OrderId = 1

SELECT @Comments

/* Delete */
-- 204
SELECT * 
FROM	sales.customers c
	INNER JOIN sales.Orders o on c.CustomerID = o.CustomerID
WHERE	o.OrderDate < '2010-01-01'

-- 205
DELETE
FROM	c
FROM	sales.customers c
	INNER JOIN sales.Orders o on c.CustomerID = o.CustomerID
WHERE	o.OrderDate < '2010-01-01'

-- 206
DECLARE @rowcount int;

SET @rowcount = 1;

WHILE @rowcount > 0
BEGIN
	DELETE	TOP (100000)
	FROM	dbo.MyVeryLargeTable;

	SET @rowcount = @@rowcount;

	WAITFOR DELAY '00:00:10';
END;

/* Output clause */

-- 207
DROP TABLE IF EXISTS output_test 
CREATE TABLE  output_test (id int,  SomeText varchar(100))

INSERT output_test (id, SomeText) VALUES (1,  'before')
INSERT output_test (id, SomeText) VALUES (2,  'before') 


UPDATE	output_test
SET		SomeText = 'after'
OUTPUT	DELETED.*, INSERTED.*

DROP TABLE IF EXISTS output_test

-- 208
INSERT output_test (id, SomeText) OUTPUT INSERTED.* VALUES (2,  'before')

-- 209
INSERT output_test (id, SomeText) OUTPUT INSERTED.id VALUES (2,  'before')

-- 210
OUTPUT	DELETED.* INTO output_test_before 

-- 211
OUTPUT	DELETED.id, DELETED.SomeText, GETDATE() INTO output_test_before (id, Sometext, ChangeTime)

/* Merge statement */

-- 212
DROP TABLE IF EXISTS Params_target

CREATE TABLE Params_target (drive CHAR(1), threshold_in_GB tinyint)
INSERT Params_target VALUES ('C',10), ('D',10), ('E',10), ('Q',10)

DECLARE @drive CHAR(1) = 'Q'
		,@threshold_in_GB tinyint = 1

IF EXISTS (SELECT * FROM  Params_target WHERE drive = @drive)
BEGIN
	UPDATE Params_target 
	SET threshold_in_GB = @threshold_in_GB
	WHERE drive = @drive
END
ELSE
BEGIN
	INSERT Params_target VALUES(@drive, @threshold_in_GB)
END

-- 213
SELECT	*
FROM	Params_target
ORDER BY drive

-- 214
-- setup
DROP TABLE IF EXISTS Params_target
DROP TABLE IF EXISTS Params_source

CREATE TABLE Params_target (drive CHAR(1), threshold_in_GB tinyint)
INSERT Params_target VALUES ('C',10), ('D',10), ('E',10), ('Q',1)

CREATE TABLE Params_source (drive CHAR(1), threshold_in_GB tinyint)
INSERT Params_source VALUES('Q',1)

--actual MERGE statement
MERGE Params_target AS TARGET
USING Params_source AS SOURCE
		ON TARGET.drive = SOURCE.drive
WHEN MATCHED AND SOURCE.threshold_in_GB <> TARGET.threshold_in_GB THEN 
	UPDATE SET threshold_in_GB = SOURCE.threshold_in_GB
WHEN NOT MATCHED BY TARGET THEN 
	INSERT (drive, threshold_in_GB) VALUES (SOURCE.drive, SOURCE.threshold_in_GB)
WHEN NOT MATCHED BY SOURCE THEN 
	DELETE
OUTPUT $action, deleted.threshold_in_GB, inserted.threshold_in_GB;

/* Determine the results of Data Definition Language (DDL) statements on supplied tables and data */

-- 215
-- add column
ALTER TABLE [dbo].[Employees] ADD Department varchar(100) NULL

-- 216
ALTER TABLE [dbo].[Employees] DROP COLUMN Department

-- 217
ALTER TABLE [dbo].[Employees] ADD Department varchar(100) NOT NULL DEFAULT 'Sales'

Msg 5074, Level 16, State 1, Line 12
The object 'DF__Employees__Depar__2F5453E4' is dependent on column 'Department'.
Msg 4922, Level 16, State 9, Line 12

ALTER TABLE DROP COLUMN Department failed because one or more objects access this column.

-- 218
ALTER TABLE [dbo].[Employees] DROP CONSTRAINT [DF__Employees__Depar__2F5453E4]

-- 219
ALTER TABLE [dbo].[Employees] ADD Department varchar(100) NOT NULL 
CONSTRAINT DF_Department DEFAULT 'Sales'

-- 220
ALTER TABLE [dbo].[Employees] ADD Department varchar(100) NULL 
CONSTRAINT DF_Department DEFAULT 'Sales' WITH VALUES

-- 221
SELECT	FirstName, LastName, Address, Salary
INTO	Employees_test
FROM	dbo.employees

ALTER TABLE [dbo].[Employees_test] ADD EmployeeID int IDENTITY

/* alter column */

-- 222
ALTER TABLE dbo.Employees ALTER COLUMN LastName int

-- 223
ALTER TABLE dbo.Employees ALTER COLUMN LastName varchar(5)

-- 224
ALTER TABLE dbo.Employees ALTER COLUMN LastName varchar(50)

-- 225
ALTER TABLE dbo.Employees ALTER COLUMN EmployeeId tinyint

-- 226
ALTER TABLE dbo.Employees ADD CONSTRAINT PK_Employeeid  PRIMARY KEY (EmployeeId)

-- 227
CREATE TABLE Departments (Department varchar(100) NOT NULL PRIMARY KEY)
INSERT Departments VALUES ('Sales')

ALTER TABLE dbo.Employees ADD CONSTRAINT FK_Department FOREIGN KEY (Department) REFERENCES Departments(Department)

ALTER TABLE dbo.Employees ALTER COLUMN Department varchar(200)

-- 228
ALTER TABLE [dbo].[Employees] ADD EmployeeNumber int NULL 
GO
UPDATE dbo.Employees SET EmployeeNumber = EmployeeID
ALTER TABLE [dbo].[Employees] ADD CONSTRAINT uq_employeenumber UNIQUE (EmployeeNumber)
GO
INSERT dbo.Employees (FirstName, LastName, Address, Salary, Department, EmployeeNumber)
VALUES('Lisa', 'Simpson','Springfield',1500.00,'Sales', NULL )

-- 229
ALTER TABLE [dbo].[Employees] DROP COLUMN EmployeeNumber 

-- 230
ALTER TABLE [dbo].[Employees] DROP CONSTRAINT uq_employeenumber
ALTER TABLE [dbo].[Employees] DROP COLUMN EmployeeNumber

-- 231
ALTER TABLE [dbo].[Employees] ADD EmployeeNumber int NULL 
EXEC sp_rename 'Employees.EmployeeNumber', 'Employee_Number'
ALTER TABLE [dbo].[Employees] DROP COLUMN Employee_Number

/* drop column */

-- 232
ALTER TABLE [dbo].[Employees] DROP COLUMN Department

-- 233
CREATE INDEX ix_department ON dbo.Employees(Department)
ALTER TABLE [dbo].[Employees] DROP COLUMN Department

-- 234
DROP INDEX ix_lastname

-- 235
ALTER TABLE table WITH CHECK CHECK CONSTRAINT ALL

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